From: Brian Lo
Newsgroups: rec.gardens
Subject: FAQ: Peppers
Date: Wed, 1 Mar 1995 09:10:47 -0800
PEPPERS
Capsicum annuum and C. frutescens
Taxonomists have only recently begun to agree regarding classification
of the domesticated species of Capsicum. Although 5 species are described,
only two, C. annuum and C. frutescens have any significance commercially in
the U.S.A. Early species separation on the basis of fruit shape, color and
position are of little taxonomic value. Flower and seed color, shape of the
calyx, the number of flowers per node and their orientation, are the primary
separating characteristics.
C. annuum is the most important domesticated species in the U.S.A. and
is the species to which all bell peppers, and all the peppers listed below
belong (unless specified otherwise.) The only C. frutescens pepper of any
significance is Tabasco. The Tabasco pepper is difficult to cross with C.
annuum types. Hot peppers may belong to any of above species and others. The
C. chinense varieties Habanero and Scotch Bonnet are considered the hottest.
See other comments under "Novelty" pepper section below.
The interest in peppers extends to their nutritive and medicinal value
in that peppers are a recognized source of Vitamins C, E and are high in
antioxidants. These compounds are associated with chemoprevention of cardio-
vascular disorders, cancers, and cataracts.
Peppers are a warm-season crop and need a long season for maximum
production. Temperature has a large effect on the rate of plant and fruit
growth and the development and quality of the red or yellow pigments. Ideal
temperature for red pigment development is between 65 and 75 F. Above this
range the red color becomes yellowish, and below it color development slows
dramatically and stops completely below 55 F.
Many excellent pepper varieties are available. Test several and select
the ones that do well under your production system, and meets your market
needs.
PUNGENCY RATINGS
The most common sensory method to determine pungency in peppers has been
an organoleptic test (Scoville, a dilution-taste procedure) with results ex-
pressed as Scoville Heat Units (SHU). The validity and accuracy of it have
been widely criticized. The American Spice Trade Association and the Interna-
tional Organization for Standardization have adopted a modified version. The
American Society for Testing and Materials is considering other organoleptic
tests (the Gillett method) and a number of chemical tests to assay for capsai-
cinoids involved in pungency. Still, the values obtained by the various tests
are often related to Scoville Heat Units.
A "National Fiery Foods Show" is held annually in Albuquerque NM. For
more information call 505/873-2187.
RECOMMENDED BELL PEPPER VARIETIES (approximately 60-70 days to first harvest
from transplants):
Bell (green): Belle Star, Yankee Bell, Bell King, North Star, Wonder
Bell, Lady Bell, Jupiter Elite, Park's Early Thickset, Bell Tower, Skipper,
Bellboy, Mission Bell, Ringer, Bell Captain, Melody, Ace Hybrid, Cardinal.
Research in the Hermiston area indicates that Jupiter Elite, Bell Tower,
Belmont, Galaxy and Skipper performed well. For trial: Camelot, Inia, Merlin,
Ranger, Summersweet, Wonderbelle, Cubico.
Note: In 1992, Bell Star and Yankee Bell produced the highest
proportion of 4-lobed, blocky peppers. Their plant growth is
more open, and not as many peppers were misshaped by growing among
branches and being confined between other fruit.
Bell (Red): Many green bell peppers turn red when fully mature. How-
ever, early, large-fruited, thick-walled varieties, demanded by the market,
are rare. Research at O.S.U. and from British Columbia indicates that Lady
Bell, La Bamba, Four Corners, Merlin, Ace Hybrid, Bellboy and Cardinal per-
formed best. Four Corners and Merlin also had thick-walls. For trial: Bell
Star, Melody, North Star, Ringer, Candice, Vidi and Predi.
Bell (yellow): Golden Belle and Astro (bright yellow), Klondike Bell
(early, high yield, has an some orange tinge), Honey Bell, Golden Cal Wonder,
Orobelle (orange-yellow). For trial: Atlantic, Summer Sweet, Marengo (Lamuyo
type); Gold Crest (small fruit) and Summer Sweet (both turn yellow or orange-
yellow quickly).
Bell (orange): Corona (performed best in OSU trials in '92). Oriole
(best in trials in British Columbia). For trial: Ariane, Kerala, Ori,
Valencia.
Purple, chocolate, and white bell peppers (see list below). These are
intermediate colors lasting 7-10 days then turning red.
Note: Many of the red, yellow and orange peppers found in the market
are greenhouse-grown from varieties specially developed for greenhouse
production.
Bell pepper varieties for greenhouse production of green or red fruit
for specialty markets (for trial only): Cubico, Flair, Plutona, Delphin.
Yellow fruit: Samantha, Gloden Flame, Golden Belle, Golden Crest, Marengo,
Orobelle, Olympic. Orange fruit: Ariane, Valencia.
--------------------------------------------------------------------------
Catagory, type of fruit attachment and pungency range:
variety name Color Stages Pungency Remarks
--------------------------------------------------------------------------
Bell; 3.5"X4.5", fruit pendant, pungency 0-100 Scoville Heat Units (SHU):
Bell King green to red sweet early
Bell Captain green to red sweet thick walls
Bell Tower green to red sweet smooth
Bellboy green to red sweet thick wall
Bellestar green to red sweet smooth
California Wonder 300 green to red sweet late, thick
Cardinal green to red sweet thick wall
Four Corners green to red sweet good shape
Jupiter green to red sweet large, mid
Lady Bell green to red sweet early
Midway green to red sweet early
Mission Belle green to red sweet v. smooth
Parks Early Thickset green to red sweet early
Parks Whopper green to red sweet med.
Pip green to red sweet large
Predi green to red sweet large, deep red
Ringer green to red sweet large, mid
Skipper green to red sweet smooth
Sweet Belle green to red sweet mid
Goldie yellow to red sweet early
Gypsy yellow to red sweet early
Yellow Belle yellow to red sweet early
Early Bountiful to yellow sweet
Golden Summer to yellow sweet late
Golden Cal. Wonder to yellow sweet thick wall
Golden Bell to yellow sweet early
Inia to yellow sweet thick wall
Klondike Bell to yellow sweet early, thick wall
Orobelle to yellow sweet thick wall
Summer Sweet 820 to yellow sweet
Golden Crest to orng-yellow sweet
Quadrato d'Oro to orng-yellow sweet
Ariane to orange sweet large, thick
Corona to orange sweet large, thick
Kerala to orange sweet large, thick
Oriole to orange sweet large, thick
Salsa RZ to orange sweet large, thick
Super Stuff yellow to orange sweet early
Catagory, type of fruit attachment and pungency range.
Variety name Color Stages Pungency* Remarks
--------------------------------------------------------------------------
Bell peppers continued:
Lorelei purple then red sweet small
Purple Beauty purple then red sweet small
Purple Belle purple then red sweet small
Violetta purple then red sweet small
Blue Jay to lavender then red sweet
Islander to lavender then red sweet
Lilac to lavender then red sweet
Chocolate Bell to chocolate sweet large fruit
Mulato to chocolate
Sweet Chocolate to chocolate sweet small fruit
Albino to white then red sweet small
Dove to white then red sweet small
Ivory to white then red sweet
Elongated Bell; (lamuyo type fruit) 3.5"x5"; pendant, pungency 0-100 SHU:
Blue Star green to red sweet large, late
Elisa green to red sweet mid
Marengo green to yellow sweet
Melody green to red sweet early
Signet green to yellow sweet early
Other peppers and their descriptions (approximately 65-105 days depending on
type).
Anaheim; fruit 2"x7"; pendant, pungency 500-3,500 SHU (most 500-1000 SHU):
Anaheim TMR green to red mild
Anaheim M green to red warm
Coronado green to red warm
New Mexico 64L green to red mild
NuMex Conquistador green to red sweet for paprika
Volcano green to red hot
Poblano/ancho; fruit heart-shaped 3"-4" x 4"-7"; pendant, 1,000-2,000 SHU.
The poblano pepper is a major type grown in Mexico, used green, red or dried
(called ancho when dried). It is commonly used for chiles rellenos:
Ancho 101 dark green to red mild thick wall
Esmeralda dark green to red ditto
New Mexican dark green to red ditto
Poblano dark green to red warm ditto
Verdano dark green to red ditto
Catagory, type of fruit attachment and pungency range.
variety name Color Stages Pungency* Remarks
--------------------------------------------------------------------------
Elongated, tapered; fruit variable shapes and sizes; pendant, 0-1000 SHU:
Banana Supreme green to yellow sweet early
Canape green to yellow sweet early
Cuban yel-grn:red orange warm
Cubanelle yel-grn:red orange mild long fruit
Hungarian Wax grnish yel:yellow warm
Sweet Banana grnish yel:yellow sweet
Cherry; about 1" diameter; upright, 100-5,000 SHU:
Cascabel green to red hot
Large Red Cherry green to red warm
Sweet Cherry green to red warm
Cayenne; fruit 0.5"x3"; pendant, 30,000-50,000 SHU. A favorite in Creole and
Cajun cooking:
Cayenne, Large Red Thick green to red firey slender
Cayenne continued...
Cayenne, Long Slim green to red firey slender
Carolina Cayenne green to red firey
Charlston Hot grn to orange to red firey to 4" long
Super Cayenne green to red firey long slender
Jalapeno; fruit 1.5"x3"; pendant, 2,500-5000 SHU. The most common hot chili
grown in the U.S.A.:
Jalapa green to red hot blunt cylind.
Jalapeno M green to red very hot thick wall
Jalapeno Hot green to red hot smooth
Mitla hybrid green to red hot thick, blunt cyl.
Tam Jalapeno #1 green to red hot thick wall
Pimento; fruit 1.5"x2.5"; pendant, 0-100 SHU:
Pimento L green to red sweet thick wall
Serrano; fruit 0.5"x2.25"; pendant, 5,000-10,000 SHU:
Serrano types dark green to red very hot small
Tabasco C. frutescens; fruit 0.25"x 1.25";pendant, 30,000-50,000 SHU:
Tabasco green to red firey small
Novelty, ornamental:
Marbles (prolific round, mix of green, yellow and red fruit), Riot (prolific
upright long fruit, mix of green, yellow and red).
Habanero (C. chinense) a firey-hot box-shaped small pepper turning from green
to orange. Although the Habanero (C. chinense) pepper has been listed as
being the hottest of all peppers, some rated at 200,000 to 300,000 SHU, not
all Habaneros are hot! Hot Habanero peppers are used to make hot bottled
sauces. They are grown mainly in Central America and the Yucatan. Other C
chinense extremely hot peppers include Scotch Bonnet (yellow), and Bahamian.
SEED COMPANIES
Abbott & Cobb Inc. POB F307, Feasterville, PA 19047
Asgrow Seed Company, POB 5038, Salinas CA 93915
De Ruiter Seeds Inc. POB 20228, Columbus, OH 43220
ENZA Zaden, POB 7, 1600 AA, Enkhuisen, Netherlands 02280-15844
Ferry-Morse Seed Co. POB 4938, 555 Codoni Ave. Modesto, CA 95352
Harris Moran Seed Co. 3670 Buffalo Rd. Rochester, NY 14624
La Marche Seeds International, POB 190, Dixon, CA 95620
Nickerson-Zwaan Seed Co. POB 1787, Gilroy, CA 95021
Petoseed Co. Inc. POB 4206, Saticoy, CA 93303
Rogers NK. POB 4727, Boise, ID 83711-4727
Royal Sluis Inc. 1293 Harkins Rd. Salinas, CA 93901
Sluis & Groot of America Inc. 124 Griffin Street, Salinas, CA 93901
Stokes Seeds Inc. POB 548, Buffalo, NY 14240
Sunseeds, 2320 Technology Pkwy. Hollister, CA 95023
The Pepper Gal. POB 12534 Lake Park, FL 33403-0534
Vilmorin Inc. POB 707 Empire, CA 95319
W. Osborne Seed Co. Int'l. 1679 Highway 99 South, Mount Vernon, WA 98273
Zenner Bros. Seed Co., Inc. 1311 S.E. Gideon St. Portland, OR 97202
Zwaan Seeds Inc. POB 397, Woodstown New Jersey 08098-0397
SOIL
Peppers grow best on well-drained, moderately fertile soils. Use a soil
test to determine fertilizer and liming requirements. Adjust soil pH to near
neutral (7.0) for maximum yields.
SEED AND SEED TREATMENT
Pepper seed numbers approximately 72,000 per pound, but bell peppers are
not normally direct seeded. Use high quality, fungicide treated seed in the
production of transplants. Some seed companies now offer "vigorized' or
"conditioned" seed which has better germination under cool soil conditions.
Peppers are sensitive to damping-off. Most chile and spice peppers are
direct-seeded.
In direct seeded plantings a pop-up fertilizer solution may be helpful.
Spray directly on the seed a solution of 2-6-0 at 1 pint per 100 lineal feet
of row (use 1/2 this rate on sandy soils). A 2-6-0 solution is equivalent to
1 part of 10-34-0 liquid fertilizer diluted with 4 parts of water.
TEMPERATURE REQUIREMENTS
Pepper is a warm-temperature vegetable and requires a long growing sea-
son. Transplants which are grown should be kept close to the following tempe-
ratures: Days:65-85 F. Nights: 60-65 F. Temperatures above 95 F may result
in flower bud drop. Highest yields are obtained when soil temperatures remain
in the 70-75 F range. Soil temperatures below 68 F may result in substantial
yield reductions.
The use of clear plastic mulch applied over herbicide treated soil, or
black plastic mulch, or the new IRT (wave-length selective) mulch is strongly
recommended.
A very few peppers are sometimes grown in greenhouses. The varieties
Bellboy, Blue Star and Mogador are reported to tolerate cool temperatures that
sometimes occur in off-season greenhouse production.
TRANSPLANT PRODUCTION AND TRANSPLANTING
It takes between 3 and 4 ounces of seed to produce enough plants for an
acre. Seeds should be planted in a heated greenhouse 6 to 8 weeks before the
field transplanting date. When growing transplants in unheated greenhouses,
cold frames or field transplant beds, 8 to 14 weeks may be necessary.
Seedlings are transplanted to other flats when the first true leaves are l l/2
in. long and spaced 2 to 2 l/2 in. apart in the greenhouse or plant bed. At
all times handle pepper seedlings with care because they are easily broken or
damaged. Harden transplants for about a week before transplanting to the
field by reducing moisture and maintaining a temperature of 55 to 65 F. This
will give resistance to wilting and sunscald.
Apply a starter fertilizer solution to the transplants when transplan-
ting to the field. Select starter fertilizers that have the highest level of
phosphorus available, such as 10-52-17, 11-48-0, 11-55-0 dry fertilizers or
10-34-0 liquid fertilizer. Make up a stock solution of 3 lbs of the dry, such
as 10-52-17, or 2 pints of liquid 10-34-0 per 50 gallons of water. Use 1/2
pint of of this stock solution per plant, applying the solution directly to
the plant roots when setting in the field. You will need about 13 fifty
gallon batches to transplant an acre.
Depth of transplanting has normally been to the top of the roots or root
ball. Research from Florida with the variety Jupiter suggests that pepper
transplants may benefit from being set deeper, up to the first true leaf.
Thirty days after transplanting, plants planted to the first true leaf had
more leaves, greater plant dry weight, more blooms and less lodging than
transplants planted to the cotyledons or to the top of the root ball. Other
data from Pennsylvania suggest caution however. Soil temperature and moisture
would be important considerations.
Greenhouse peppers are sown October through February for harvest of red
fruit approximately 5 months later, March through July.
SPACING
Space rows, or pairs of rows about 18-36 inches apart. Plants should be
12-l8 in. apart in the row and between pairs of rows, depending on method of
transplanting and transplanter capability. These spacings represent a plant
population of from 10,000 to 29,000 per acre
Leave roadways across the field at about 150 foot intervals to facili-
tate carrying pails of peppers to collection locations if a harvester aid and
bulk loading is not used.
When using plastic mulch, plant 2 rows of peppers per mulch strip, using
36 inch wide platic. Space plastic strips 5-6 feet apart. Use drip irriga-
tion tubing under the plastic mulch between the two pepper rows, with drip
emmiters at 9 inch spacing down the row.
In greenhouse production, allow 3.0 to 3.5 square feet/plant. Plants
are pruned to a 2-stem training system. After 10-12 leaves have developed,
the plant forks, and a flower develops at the fork. Two or three branches are
produced, of which the two strongest are chosen for further production. These
must be supported by a string or post, and all subsequent branches removed
after the 2nd leaf. Restrict fruit set on the two stems until at least 3 or 4
leaf axils have formed or stem growth and subsequent fruit set will be greatly
reduced.
FERTILIZER
A soil test is the most accurate guide to fertilizer requirements. The
following recommendations are general guidelines for loamy soils or when
organic matter exceeds 2 1/2% :
Nitrogen: 75-100 (N) lb/acre.
Side-dress with 35-50 lb/acre of nitrogen after the first flowers are
set. Where mulching and trickle irrigation are practiced, additional
nitrogen can be fed through the trickle irrigation system at l5 lb./acre when
the first fruit begins to set and an additional l5 lb./acre four weeks after.
To prevent clogging or plugging from occurring use soluble forms of nitrogen
(urea or Ammonium nitrate) and chlorinate the system once a month with a l0 to
50 ppm chlorine solution. Chlorinate more frequently if the flow rate
decreases.
Phosphate: 100-150 (P2 O5) lb/acre
Potash: 100-200 (K2 O) lb/acre depending on soil test.
Sulfur: 30-35 (S) lb/acre
pH: Add lime if below 6.0
GROUND MULCHES AND ROW COVERS
The use of clear plastic mulch applied over herbicide treated soil, or
black plastic ground mulch is recommended. The use of ground mulch increases
soil temperature, conserves soil moisture, and controls weeds, increasing
yields and is strongly recommended especially for production in western
Oregon. A new generation of plastic mulch films allows for good weed control
together with soil warming that is intermediate between black plastic and
clear film. These films are called IRT (infra-red transmitting) films. They
are more expensive than black or clear films, but may be cost-effective where
soil warming is important. (See also section on spacing).
Spunbonded polyester and perforated polyethylene row covers may be used
for 4 to 6 weeks immediately after transplanting depending on temperature.
Research in Illinois with the varieties "Lady Bell" and "Bell Boy", over a
three year period, indicates that covers should be removed after 650-675 heat
units (using a base temperature of 50 F.) have been accumulated. Heat units
should be based on temperatures recorded outside the covers but nearby and
calculated as: the sum of (daily high+daily low)/2-50 F.
Row covers increase heat unit accumulation by 2 to 3 times over ambient.
Two to four degrees of frost protection may also be obtained at night. Soil
temperatures and root growth are also increased under row covers as are early
yields, and in some cases total yields. Research from Connecticut indicates
that the use of row cover and plastic mulch is particularly cost effective
when growing red, yellow or orange bell peppers for the fresh market.
IRRIGATION
Apply water uniformly to reduce incidence of blossom end rot. Irrigate
carefully after fruit ripens to reduce fruit decay. A total of 12-15 inches
may be needed in western Oregon and 25-30 inches in eastern Oregon, depending
on planting date and harvest season. Approximate summer irrigation needs for
the Hermiston area have been found to be: 3.5 inches in May, 5.0 in June, 7.5
in July, and 7.0 in August.
HARVESTING, HANDLING AND STORAGE
Yields of 15 to 25 tons/acre of bell peppers may be obtained for
processing. Fresh market yields may range from 500 to 1000 28 lb. cartons per
acre. Pimento and dried chili pepper yields range from 2 to 3 tons/acre.
Pepper yields are greatly influenced by the number of harvests and season.
Bell pepper types are generally hand harvested as green mature fruits.
Maturity is determined when fruits are smooth and firm to the touch (a
function of wall thickness). Bell peppers for fresh market must also be 3
inches in diameter and not less than 3 1/2 inches long to qualify as USDA
Fancy. They can also be harvested red, which are considerably sweeter and
more flavorful.
Cherry types are harvested as both green and red fruits, and the banana
types are generally harvested as yellow mature peppers. Jalapano and some
cherry peppers have been machine harvested successfully in Michigan and
California. Machine harvesting may be successful with other types especially
where the peppers are intended for processing. Peppers intended for machine
harvest need to be grown on raised beds in order to be harvested successfully.
When red peppers are desired, a foliar spray of Ethephon (Ethrel) may be
used to promote early, uniform ripening and coloring, or to ripen the par-
tially ripe fruit remaining at the end of the harvest season. Check the
Ethephon label for complete instructions and regulations.
STORAGE (quoted from USDA Ag. Handbook #66):
Sweet Peppers:
Store sweet peppers at 45 to 55 F and 90 to 95 % relative humidity.
Sweet, or bell, peppers are subject to chilling injury at temperatures below
45 F, and temperatures above 55 F encourage ripening and spread of bacterial
soft rot. Bell peppers should not be stored longer than 2 to 3 weeks even
under the most favorable conditions. At 32 to 36 F peppers usually develop
pitting in a few days. Peppers held below 45 F long enough to cause serious
chilling injury also develop numerous lesions of alternaria rot. Alternaria
causes the calyx to mold and decay. Holding at 40 F and below predisposes
peppers to Botrytis decay also.
Rapid precooling of harvested sweet peppers is essential in reducing
marketing losses, and this can be done by forced-air cooling, hydrocooling or
vacuum cooling. Properly vented cartons are recommended to facilitate forced-
air cooling. If hydrocooling is used, care should be taken to prevent the
development of decay.
Sweet peppers prepackaged in moisture-retentive films, such as perforat-
ed polyethylene, have a storage life at 45 to 50 F up to a week longer than
non- packaged peppers. The use of film crate liners can help in reducing
moisture loss from the fruit.
It is commercial practice to wax peppers; only a thin coating should be
applied. Waxing provides some surface lubrication, which not only reduces
chafing in transit but also reduces shrinkage; the result is longer storage
and shelf life. Senescence of sweet peppers is hastened by ethylene. There-
fore, it is not a good practice to store peppers with apples, pears, tomatoes,
or other ethylene producing fruits in the same room.
Low-oxygen (3 to 5 %) atmospheres retard ripening and respiration during
transit and storage. High concentrations of carbon dioxide delay the loss of
green color. However, high carbon dioxide also causes calyx discoloration.
Chili and Other Hot Peppers:
Storage temperature depends on use; see text. A humidity of 60 to 70%
is recommended. Chili peppers are usually picked when ripe and are then dried
and allowed to equalize in moisture content in covered piles. Water is
usually added to the peppers after drying to reduce brittleness. They are
then packed tightly into sacks holding 200 or more pounds and are generally
stored in non-refrigerated warehouses for up to 6 months. The temperature of
the warehouses depends to some extent on their construction and the way in
which they are managed but chiefly on the outside temperature (50 to 75 F).
Insect infestation is a major storage problem. In southern states, chili and
other hot peppers are dried, packaged, and then stored at 32 to 50 F until
shipped to processing plants. Storage at low temperatures aids in retarding
the loss of red color and in slowing down insect activity.
The moisture content of chili and other hot peppers when stored should
be low enough (10 to 15 %) to prevent mold growth. A relative humidity of 60
to 70 % is desirable. With a higher moisture content the pods may be too
pliable for grinding and may have to be re-dried. With lower moisture content
(under 10 %) pods may be so brittle they shatter during handling; this causes
losses and the release of dust, which is irritating to the skin and respirato-
ry system.
The use of polyethylene bags allows better storage and reduces the dust
problem. The liners ensure that the pods maintain a constant moisture content
during storage and up until the time of grinding; thus, they permit successful
storage or shipment under a wide range of relative humidities. Packed in this
manner, peppers can be stored 6 to 9 months at 32 to 40 F.
Manufacturers of chili and other hot pepper products hold part of their
supply of the raw material in cold storage at 32 to 50 F, but they prefer to
grind the peppers as soon as possible and store them in the manufactured form
in airtight containers.
Freshly harvested chili or other hot peppers should be stored under the
same temperature and humidity conditions as those for sweet peppers.
PACKAGING
Bell peppers are packaged in 25-30 lb. l l/9 bushel containers or 30 lb.
cartons. Chili peppers and yellow types are packaged in 16-25 lb. lugs or 10-
20 lb. cartons.
^L PEST CONTROL FOR PEPPERS
THE PESTICIDES LISTED BELOW, TAKEN FROM THE PACIFIC NORTHWEST PEST
CONTROL HANDBOOKS, ARE FOR INFORMATION ONLY, AND ARE REVISED ONLY ANNUALLY.
BECAUSE OF CONSTANTLY CHANGING LABELS, LAWS, AND REGULATIONS, OREGON STATE
UNIVERSITY CAN ASSUME NO LIABILITY FOR THE CONSEQUENCES OF USE OF CHEMICALS
SUGGESTED HERE. IN ALL CASES, READ AND FOLLOW THE DIRECTIONS AND PRECAUTION-
ARY STATEMENTS ON THE SPECIFIC PESTICIDE PRODUCT LABEL.
USE PESTICIDES SAFELY!
Wear protective clothing and safety devices as recommended on the label.
Bathe or shower after each use.
Read the pesticide label--even if you've used the pesticide before. Follow
closely the instructions on the label (and any other directions you have).
Be cautious when you apply pesticides. Know your legal responsibility as a
pesticide applicator. You may be liable for injury or damage resulting from
pesticide use.
WEED CONTROL
When black plastic ground mulch is not used, cultivate as often as
necessary when weeds are small. Proper cultivation, field selection and
rotations can reduce or eliminate the need for chemical weed control.
THE WEED TREATMENTS LISTED BELOW ARE TAKEN FROM THE PACIFIC NORTHWEST
WEED CONTROL HANDBOOK, AND ARE FOR INFORMATION ONLY. CONSULT PRODUCT LABELS
FOR CURRENTLY LEGAL REGISTRATIONS, RATES, AND COMPLETE INSTRUCTIONS.
STALE SEEDBEDS FOR VEGETABLE PRODUCTION
Stale seedbeds are sometimes used for vegetable production when other selec-
tive weed control practices are limited or unavailable. The concept depends
on controlling the first flush of emerged weeds before planting or emergence
of the crop followed by minimal soil disturbance which reduces subsequent weed
flushes during establishment of the crop. Following establishment, other weed
control practices including cultivation or use of other herbicides can be
used.
1. Prepare a seedbed, preferably 2 to 3 weeks before planting to achieve
maximum weed seed germination near the soil surface. Soil temperatures
and moisture must be reasonable or results will be erratic.
2. Plant the crop with minimum soil disturbance. Otherwise, new weed seed
will be exposed to favorable germinating conditions.
3. Just before or after planting but before crop emergence, treat the
field by flaming or with herbicide to kill all germinated or exposed
weeds.
Weed Treatment Active Ingredient Per Acre and Application Comments
------------------------------------------------------------------------------
Flaming
Use liquid propane or similar fuel-burning equipment to quickly sear the
weeds, but not consume them with flame.
------------------------------------------------------------------------
paraquat 0.625 to 0.94 lb ai/A
Gramoxone Extra
(see remarks)
Restricted-use pesticide. Do not ingest or inhale spray mist. Wearing
protective face shields, respirators, and clothing is advised. Apply
during or after planting, but before crop emergence. Add a nonionic
surfactant or crop oil concentrate according to label specifications,
taking care to avoid anionic formulations that react in the tank to form
insoluble precipitates. Exposed crop plants will be killed. Do not
apply preplant or preemergence to soils lacking clay minerals, such as
peat, muck, pure sand, or artificial planting media. (Acts as contact;
absorbs energy produced by photosynthesis forming peroxides that disrupt
living cells.)
______________________________________________________________________________
PREEMERGENCE SOIL-APPLIED
DIRECT-SEEDED AND TRANSPLANTS
Weed Treatment Active Ingredient Per Acre and Application Comments
------------------------------------------------------------------------------
trifluralin 0.5 to 1.0 lb ai/A
Treflan
(transplanted pepper only)
Apply before transplanting and incorporate within 24 hours by cross-
disking or by using a PTO rotary tiller. Transplants may be set im-
mediately. Spray only once and avoid overlaps. Use lower rates on
light or coarse textured soils low in organic matter. Consult label for
planting crops within 12 months. (Inhibits mitosis, primarily of
shoots).
------------------------------------------------------------------------
napropamide 1 to 2 lb ai/A
Devrinol
Apply and incorporate uniformly 1 to 2 inches deep. Use lower rates on
light, sandy, or coarse-textured soils. Following harvest, deep
moldboard plowing or disk plowing must be completed before planting
succeeding crops. (Inhibits roots of seedlings).
______________________________________________________________________________
TRANSPLANTS ONLY
Weed Treatment Active Ingredient Per Acre and Application Comments
------------------------------------------------------------------------------
DCPA 9 lb ai/A
Dacthal
Apply 4 to 6 weeks after transplanting to weed-free soil. Soil should
be moist and additional water applied for activation. Performs poorly
in western Oregon and Washington. Consult label for planting sensitive
crops within 12 months. Results can be improved with overhead irriga-
tion applied immediately after spraying. (Inhibits mitosis).
______________________________________________________________________________
ACTIVATED CHARCOAL SEED PROTECTION
Several Pacific Northwest grass seed crops are protected from herbicide injury
with the use of activated charcoal which adsorbs and detoxifies or inactivates
the herbicide. In vegetables, activated charcoal can be mixed with horticul-
tural grade vermiculite and applied as an anticrustant/seed protectant. The
activated charcoal vermiculite mix is placed within the seed furrow using a
positive feed device. Herbicides must not leach excessively or move readily
from crop roots into the plant. Although crop safety can be enhanced, weeds
emerging from within the treated area also are protected.
Another use for activated charcoal involves seed protection from herbicides
that leach into the seed zone from excessive rainfall. Seed coatings of
activated charcoal would reduce the active concentration of herbicide at or
very near the seed during the germination process.
Activated charcoal/vermiculite mix: Thoroughly mix 1 lb activated
charcoal/ft3 of number 2 or 3 grade horticultural
vermiculite. If severe dustiness is a problem, add a
small amount of water. Apply 1 ft3 of mixture/600 ft.
of seeded row or approximately 15 cu.ft/A. Fill the
seed furrow using a positive feed applicator and press
with a press wheel.
______________________________________________________________________________
POSTEMERGENCE
Weed Treatment Active Ingredient Per Acre and Application Comments
------------------------------------------------------------------------------
Sethoxydim 0.29 lb ai/A
Poast
Identify susceptible grasses and apply at optimum growth stage listed on
the label. Add 2 pints/A nonphytotoxic crop oil concentrate to improve
leaf absorption. Erratic control often occurs when grasses are stunted
or stressed from drought, high temperatures, or low fertility. Resis-
tant grasses include annual bluegrass and all fine fescues, whereas
quackgrass can be suppressed. Do not apply within 20 days of harvest,
nor exceed 4.5 pints/A per season. (Inhibits fatty acid production,
cell membranes, and new growth.)
______________________________________________________________________________
______________________________________________________________________________
INSECT CONTROL
Proper rotations and field selection can minimize problems with insects.
THE PESTICIDES LISTED BELOW ARE TAKEN FROM THE PACIFIC NORTHWEST INSECT
CONTROL HANDBOOK, AND ARE FOR INFORMATION ONLY. CONSULT PRODUCT LABELS FOR
CURRENTLY LEGAL REGISTRATIONS, RATES AND COMPLETE INSTRUCTIONS.
Insect and Description Control, Active Ingredient Per Acre
---------------------------------------------------------------------------
Armyworms, Cutworms, Loopers. permethrin - 0.1 to 0.2 lb
Loopers only.
Lannate - 0.45 lb
Small to large larvae that feed
on stems, leaves, and fruit. carbaryl - 2.0 lb Cutworms
and fall armyworm only.
Asana - 0.03 to 0.05 lb
Bacillus thuringiensis - 1 to 2
qt. Use a spreader-sticker to
enhance control.
Orthene - 0.5 to 1 lb
Bell peppers only.
---------------------------------------------------------------------------
Green peach aphid endosulfan - 0.5 to 1 lb
Myzus persicae
Phosdrin - 0.25 lb
Yellowish, pink to pale green
plant louse. malathion - 1.25 to 1.5 lb
Where aphids have become phosphamidon - 0.5 lb
resistant to most organic phos-
phate insecticides, endosulfan Dibrom - 1 lb
is the preferred material.
dimethoate - 0.25 to 0.33 lb
Lannate - 0.45 lb
Metasystox-R - 0.5 lb
Orthene - 0.5 to 1 lb
bell peppers only
diazinon - 0.25 lb
Vydate L - 0.5 to 1.0 lb
---------------------------------------------------------------------------
Garden symphylan Dyfonate - 2 to 4 lb. Preplant
Scutigerella immaculata soil treatment. Do not rotate
with carrots.
Small, white, centipede-like
animals active in soil. parathion - 6 lb - replant soil
treatment.
Telone II or C-17 preplant
---------------------------------------------------------------------------
Flea beetles including azinphosmethyl - 0.5 lb
Western potato flea beetle
Epitrix subcrinita carbaryl - 1 lb
Small, oval, shiny bronze jump- Asana - 0.03 to 0.05 lb
ing beetles. Chew small circu-
lar holes in foliage. methoxychlor - 1.75 to 2.25 lb
rotenone - 0.35 to 0.5 lb
endosulfan - 0.5 to 1 lb
permethrin - 0.1 to 0.2 lb
Bell peppers only.
---------------------------------------------------------------------------
Spider mites dicofol - 0.375 to 0.75 lb. Do
Tetranychus spp. not feed.
Tiny, spiderlike animals found Phosdrin - 0.5 lb
on undersurfaces of foliage.
---------------------------------------------------------------------------
Wireworms diazinon - 3 to 4 lb
Limonius spp.
Dyfonate - 4 lb
Brown, jointed larvae of click Do not rotate with carrots.
beetles. Kill young plants, in-
jure older ones. Telone II or C-17 preplant
__________________________________________________________________________
__________________________________________________________________________
DISEASE CONTROL
Proper rotations, field selection, sanitation, spacings, fertilizer and
irrigation practices can reduce the risk of many diseases. Fields can be
tested for presence of harmful nematodes. Using seed from reputable seed
sources reduces risk from seed born diseases.
THE PESTICIDES LISTED BELOW ARE TAKEN FROM THE PACIFIC NORTHWEST DISEASE
CONTROL HANDBOOK, AND ARE FOR INFORMATION ONLY. CONSULT PRODUCT LABELS FOR
CURRENTLY LEGAL REGISTRATIONS, RATES AND COMPLETE INSTRUCTIONS.
PEPPER -- MOSAIC VIRUSES
Cause: Several viruses transmitted by aphids, including alfalfa mosaic virus,
potato virus y, pepper mottle virus, tobacco etch virus, and cucumber mosaic
virus. Tomato spotted wilt virus also infects pepper but is transmitted by
thrips.Symptoms: Bright yellow mottle, ringspots, and line patterns on both
leaves and fruit. Fruit and plants are stunted, and sometimes exhibit lateral
leaf rolling. Many of these viruses overwinter in perennial legumes such as
alfalfa and various clovers. Several common weeds are hosts of some of the
viruses.
~Control: Plant as far as possible from alfalfa fields, clover fields, and
permanent pastures containing clovers. Keep area around fields as weed-free
as possible. Aphid control is helpful but will not provide perfect control.
If tomato spotted wilt is a problem, control of thrips will be of some help.
---------------------------------------------------------------------------
PEPPER -- ANTHRACNOSE
Cause: Gloeosporium, a fungus found on both peppers and eggplants. This
fungus (like many other anthracnose fungi) is saprophytic during part of its
life cycle and may survive from year to year in the soil crop refuse.
Symptoms: Round sunken spots appear on both green and ripe fruits. Spores
develop on the infections often in radiating circles around the center, which
later may contain masses of pink spores. The seed may be infected and often
seedlings have the disease, which later moves into the developing foliage.
Such infections are often unnoticed until the fruits start to grow, at which
time the fruit rot phase may become serious.
~Control:
1. Destroy all plant refuse by burning or deep plowing.
2. Rotate crops.
3. Spray fixed copper fungicide. See product label.
4. Spray Maneb at 1.2 to 1.6 lb ai/A. Do not apply more than 9.6 lb
ai/A/season. Do not apply within 7 days of harvest.
---------------------------------------------------------------------------
PEPPER -- BACTERIAL SPOT
Cause: A bacterium Xanthomonas vesicatoria, that is seedborne and frequently
comes with transplants. It will live over winter in infected debris and is
spread by irrigation. Pickers and equipment also spread the disease, particu-
larly when the plants are wet.
Symptoms: Water-soaked spots on leaves that turn gray with black centers.
They frequently are surrounded by a yellow halo. They later fall out, leaving
holes apaproximately 0.25 inch in diameter that give the plant a ragged look.
Fruit spots are at first water-soaked and later become raised and scabby.
~Control:
1. Plant disease-free seed or transplants.
2. Limit overhead irrigation or, better, produce peppers under furrow or drip
irrigation.
3. Do not pick or cultivate plants when they are wet.
Chemical control:
If disease is present, spray with fixed copper during wet period. Several
materials are labeled. See product label for rates.
Residue: Copper -- exempt.
---------------------------------------------------------------------------
PEPPER -- CERCOSPORA LEAF SPOT
Cause: Cercospora melongenae (mostly on eggplant), Cercospora capsici (mostly
on pepper), fungi. These organisms survive the winter on dead plant parts.
Symptoms: Leaf spot infections on eggplant are small, chlorotic, gray turning
to brown, with tiny, dark specks containing spores arranged in circular
fashion. Eggplant fruits are not attacked. Leaf spot on pepper is at first
water-soaked and up to inch in diameter, later becoming tan in shade with a
dark marginal ring. Centers may often drop out as they age. Spots develop on
stems and petioles. When numerous, the leaves turn yellow and may drop or
wilt. Defoliation is often serious, exposing peppers to sunscald.
~Control:
1. Destroy by burning or deep burying old pepper and eggplant refuse.
2. Use seed from disease-free areas.
3. Rotate crops.
4. Spray Maneb at 1.2 to 1.6 lb ai/A. Do not apply more than 9.6 lb
ai/A/season. Do not apply within 7 days of harvest.
5. Spray fixed copper fungicide. See product label.
--------------------------------------------------------------------------
PEPPER -- COMMON (Tobacco) MOSAIC
Cause: A virus spread by aphids and mechanical means. It overwinters on wild
perennial hosts.
Symptoms: Varying types of yellow and green leaf mottling accompanied by
curling and leaf distortion are displayed. In the early season, plants are
frequently stunted and very few fruits develop. Plants infected later in the
season (during or after blossom) show slight mottling only. Infected fruits
are often yellowed, shriveled, mottled, irregularly shaped, and dwarfed in
size.
~Control:
1. Maintain rigid weed control in nearby plantings.
2. Controlling aphid vectors with insecticides may help reduce spread.
3. Do not smoke around the plants, particularly in the greenhouse.
4. Wash hands after handling infected plants.
5. Rouge infected plants early.
6. Resistant cultivars include `Yolo-wonder', `Pennbell', `Bell Boy',
`California Wonder 300', `Orobelle', `Bell Tower', `Elisa', `Marquis', `Belle
Star', `Big Belle', `Four Corners', `Sweet Belle', `Bolero', `Lamuyo',
`Emerald Giant', `Prima Belle', `Lady Bell', `La Bamba', `Jupiter' and
`Keystone Resistant Giant'. Hot types that are resistant include `Anaheim TMR
23', `Caloro', `Santa Fe Grande', `Tam Jalapano', `Tam Serrino Hidalgo', and
`Gold Spike'.
---------------------------------------------------------------------------
PEPPER -- LATE BLIGHT
See Potato and Tomato - Late Blight
---------------------------------------------------------------------------
PEPPER -- ROOT ROT
Cause: Phytophthora capsici, a fungus. This soil-inhabiting organism causes
root rot in pepper and eggplants and is most active in moist, warm weather.
Symptoms: At soil level, dark-greenish, water-soaked spots occur which often
girdle the stem, causing the plants to wilt and die. Foliage leaf spots
develop, which are often water-soaked and irregular in shape, later becoming a
light-brown shade. The fruit shows similar spots often enlarging to cover the
entire fruit, which later dries and becomes mummied.
~Control:
1. Plant only in clean soil where the disease has not occurred.
2. Use disease-free seed.
3. Practice light irrigation and crop rotation.
4. Ridomil 2E can be used to control this problem. A full program consists
of a preplant application followed by two postplant applications. See product
label.
---------------------------------------------------------------------------
PEPPER -- VERTICILLIUM WILT
Cause: Verticillium dahliae, a fungus organism. The Verticillium wilt organism
is a widespread soil inhabitant which affects a wide range of herbaceous and
woody plants.
Symptoms: Infected plants show a stunting of growth accompanied by yellowing
and inward rolling of the leaves. The disease development on eggplant begins
with a yellowing of the lower leaves, reduced size and vascular discoloration.
It is seedborne in the eggplant. The fungus gains entry through the root
system, and progress in the plant is primarily through the vascular system.
~Control:
1. Old crop remains should not be left on the field or added to the compost
pile, as this encourages future infections.
2. Crop rotation with nonsusceptible grasses and grains may be of some small
value, but nothing can really be done to eradicate this disease.
3. Avoid tomatoes and potatoes in any rotation, as these are favorite hosts.
4. There are as yet no resistant varieties.
______________________________________________________________________________
______________________________________________________________________________
---------------------------------------------------
---------------------------------------------------
This information was adapted by the Oregon State
University Extension Service from Oregon and
Pacific NW publications as well as other vegetable
production guidelines from public institutions
in the U.S. and Canada. These guidelines are
intended as a general guide for Oregon commercial
vegetable producers. Address comments of questions
to your County Extension Agent or Dr. N. S.
Mansour, Department of Horticulture, Oregon State
University, Corvallis, OR 97331.
---------------------------------------------------
|
|
Disclaimer: The file contained in the
box above or displayed in a separate window from a link in the
box above is NOT owned nor implied to
be owned by BeYoND THe iLLuSioN. Most files at BeYoND THe
iLLuSioN are originally from public Bulletin Board Systems
(BBS) which were popular in the days before the Internet or
from gopher, web, and FTP sites from the early days of the
Internet which no longer exist today. Essentially, all files
were acquired from the public domain in one for or another.
However, there have been occasions when copyright protected
material has appeared on BeYoND THe iLLuSIoN without permission
of the copyright holder. In these instances, we have and will
continue to remove the copyright protected file as soon as it
is brought to our attention. This can now be done using our Report Copyright Material form. Fill
out the form, and the webmaster will be notified of the
situation.
There are also times when files found on BeYoND THe iLLuSioN
have a real home somewhere else on the Internet. In these
instances, we will gladly replace the file with a link to its
true home whenever it is brought to our attention. If you know
of the true home of any of these files, you can use our Report Original URL form to bring it yo our
attention.
|