Subject: FAQ: Okra

From: Brian Lo <[email-masked]>
Date: Wed, 8 Mar 1995 13:46:10 -0800

OKRA
                          Abelmoschus esculentus

      Okra is not well adapted to Oregon climatic conditions, requiring high
soil temperatures and high day and night temperatures for best production. 
Okra may be grown in the warmer parts of the state when special efforts are
made to provide the proper environmental conditions.  This would include the
use of plastic mulch and wind breaks to improve temperatures around the plant
and in the soil. 

VARIETIES

Green types:

      Blondy, 48-50 days, dwarf plant 3'high, spineless, ribbed, lime-green. 
Annie Oakley, 52 days, plants 3-4'tall.  Prelude, 52 days, plants 3-4'tall. 
Clemson Spineless, 55 days, plants 5' tall, pods 5-6"long, large diameter,
most commonly available variety.  Emerald, 55 days, plants 5' tall, pods to
8"long, small diameter.  Perkins Mammoth Long Pod, 60 days, plants 6 to 10'
tall, pods 7-8" long, intense green.

Red types:

      Red Okra; 55 to 65 days, 3 to 4 feet tall, bushy plants with 6 to 7"
pods.  Red Velvet; similar to Red Okra.

SEED COMPANIES

Asgrow Seed Company, POB 5038, Salinas CA 93915
Ferry-Morse Seed Co. POB 4938, 555 Codoni Ave. Modesto, CA 95352
La Marche Seeds International, POB 190, Dixon, CA 95620
Stokes Seeds Inc. POB 548, Buffalo, NY 14240

SOIL

      Well drained, sandy soils are preferred.  Addition of manure or other
organic material is usually beneficial on such light textured soils.  Okra
grows best in neutral to slightly alkaline soils, pH 6.5-7.5.

TEMPERATURE REQUIREMENTS

      Okra is a tropical plant requiring warm growing conditions.  Commercial
production is recommended only in the warmest portions of the state.  Night
temperatures should be above 55 F for good growth.

      Minimum soil temperature for germination is 60 F.  Optimum soil tempera-
ture range is 75-90 F.

PLASTIC ROW COVERS AND MULCHES

      Black plastic mulch will increase soil temperatures, control weeds, and
conserve moisture, increasing yield and earliness. 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.

      Spun bonded polyester and polypropylene, and perforated polyethylene row
covers may be used for 4-8 weeks immediately after transplanting.  Covers
should be removed when plants begin to flower to permit proper pollination. 
Row covers can increase heat unit accumulation by 2-3 times over ambient.  Up
to 4 F of frost protection may also be obtained at night.  Soil temperatures
and root growth can also be increased under row covers as are early yields,
and in some cases total yields.

SEEDING

      Okra seed numbers approximately 8,000 per pound.  Use approximately 8-12
lbs. seed/acre.  Plant 1" deep, 4-6 seeds/foot of row.  Thin to desired spa-
cing when plants are 3" tall.

      Germination many be enhanced by soaking seeds several (4-6 hours) hours
or overnight immediately before planting.  The seed will need to be surface
dried for mechanical planting.

SPACING

      Rows 36-48" apart, 12-24" between plants.  Tall or spiny cultivars
require wide spacing.

TRANSPLANTING

      Growers interested in early fresh market or in short growing season
areas may find it profitable to transplant.  Sow seeds in 2" pots or cell
packs, 3 seeds per pot, 1/4" deep, 4-5 weeks ahead of transplanting.  Thin to
1 plant per pot or cell.

FERTILIZER

      The following are general recommendations.  Before planting apply:

           Nitrogen:  30-50 lb./acre applied at planting.  Side dress with an
additional 35-50 lbs. N/acre when plants are 8-10" tall, or use 25 lb./acre
nitrogen after first fruit set and again after 4-6 weeks at the same rate. 
Adequate nitrogen is necessary to ensure a long harvest period, however
excessive rates are to be avoided as they can cause okra to become excessively
vegetative.

           Phosphorus:  50-100 lbs./acre, all applied at, or before planting.

IRRIGATION

      Okra requires adequate soil moisture throughout its entire growing
period if optimum growth and yield are to be obtained.  Avoid heavy early
irrigations as these can cool the soil and slow development.

HARVESTING, HANDLING AND STORAGE

      Okra pods should be harvested while still tender and before the seeds
are half grown.  This is usually 5-6 days after flowering.  Pods with tips
that will bend between the fingers without breaking are too tough for use as
fresh fruit.  Consumer preference demands pods 2 1/2"-3 1/2" in length.  Okra
should be harvested about 3 times each week.  Regular picking increases yield. 
Remove and discard old pods from the plant as such pods will retard pod set
and reduce total yield.  Under good conditions 300 to 400 lbs. might be
obtained per picking per acre.  In the warmer, longer season areas of Oregon
(the Columbia and Snake River areas) okra might be harvested over a 50 to 60
day season. 

      Okra plants and pods may have small spines to which some people are
allergic.  Pickers should wear gloves and long sleeved shirts as skin protec-
tion.

      STORAGE (quoted from USDA Ag. Handbook # 66):

      Hold okra at 45 to 50 F and 90 to 95 % relative humidity.  Okra deter-
iorates rapidly and is normally stored only briefly to hold for marketing or
processing.  Large quantities are canned, frozen or brined.  It has a very
high respiration rate at warm temperatures and should therefore be promptly
cooled to retard heating and subsequent deterioration.

      Okra in good condition can be stored satisfactorily for 7 to 10 days at
45 to 50 F.  At higher temperatures toughening, yellowing, and decay are
rapid.  A relative humidity of 90 to 95 % is desirable to prevent shriveling. 
At temperatures below 45 F okra is subject to chilling injury, which is
manifested by surface discoloration, pitting, and decay.  Holding okra for 3
days at 32 F may cause sever pitting.  Contact or to ice will cause water
spotting in 2 or 3 days.

      Fresh okra bruises easily, the bruises blackening within a few hours.  A
bleaching type of injury may also develop when okra is held in hampers for
more than 24 hours without refrigeration.  Storage containers should  permit
ventilation.

      Prepackaging in perforated film is helpful. both to prevent wilting and
physical injury during handling.  Results of a packaging study suggest that 5
to 10 % carbon dioxide in the atmosphere lengthens shelf life by about a week. 
Higher concentrations of carbon dioxide caused off-flavors.

PACKAGING

      Okra is shipped in bushel hampers or crates, holding 30 lb. net; 5/9
bushel crates, 18 lb. net; 12 quart baskets, 15-18 lb. net; or loose pack in
cartons or LA. lugs, 18 lb. net.

                           PEST CONTROL FOR OKRA

     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

     The Pacific Northwest Weed Control Handbook has no control entries for
this crop.  

     Cultivate as often as necessary when weeds are small.  Proper culti-
vation, field selection and rotations can reduce or eliminate the need for
chemical weed control.  

INSECT CONTROL

     The Pacific Northwest Insect Control Handbook has no control entries for
this crop.  

     Proper rotations and field selection can minimize problems with insects.

DISEASE CONTROL

     The Pacific Northwest Disease Control Handbook has no control entries for
this crop.  

     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 sources
reduces risk from "seed born" diseases.

     Use spacings and irrigations practices that minimize diseases and allow
for cultivation.  Choose fields free of perennial weeds and where related 

crops have not been grown for the previous three years to minimize problems
with diseases and weeds.   

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          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 or questions
          to your County Extension Agent or Dr. N. S. Mansour
          Department of Horticulture, Oregon State University
          Corvallis, OR 9733l.
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