Celery seed numbers approximately 960,000 per pound. It is advisable to use
only treated seed for transplant production. Celery is not commonly direct
seeded. Some companies provide vigorized or primed seed that germinates
uniformly and rapidly. Use only highest quality sized and density graded seed.
Seeding and Transplant Production
Direct seeding is not recommended due to the difficulty in establishing a
uniform stand and the long time needed to harvest. Direct seeding is possible
where an excellent seedbed can be made and crusting prevented by solid set
irrigation. Pelleted, vigorized seed and precision seeding should be used. Plug
transplants are available from specialized transplant producers and should be
used. For production of on-farm greenhouse transplants, broadcast seed into a
suitable soil mix or sterilized soil, transplant to other flats when seedlings
are 1 to 2 in. tall. Move plants to the field when seedlings are 4 to 5 in.
tall and temperatures are above 55 F. Seedlings larger than 4 inches may show
more bolting and be later maturing. For later crops, one may plant in open beds
about May 1 and transplant to prepared fields in July. Clipping the leaves of
the seedling results in greater uniformity, stronger stems, and allows more
light to reach the slower-growing smaller seedlings. In field or greenhouse
transplant production, care must be exercised to protect plants from mean daily
temperatures below 55 F. for extended periods of time (10-14 days), and
particularly below 45 F. for even short periods. Such exposure preconditions
celery to bolting and may result in severe losses in yield and quality.
Transplanting
Machine transplant seedlings carefully to ensure a more uniform depth of
planting, even growth. Never allow celery plant roots to dry out during
handling and transplanting. Rows should be spaced 20 in. apart with plants
spaced 6-8 in. apart within the rows. If paired rows are used, use 12-14 inches
between pairs of rows and space pairs 40 inches center-to-center. Using
excessive spacing will result in plants that are more open than desired.
Fertilizer and Nutrient Management
A soil test is the most accurate guide to fertilizer requirements. The
following recommendations are general guidelines that are applicable in the
United States: Mineral soils: Add lime to maintain a pH above 6.0 on mineral
soils. Transplant Seed-beds - Broadcast and rotate in a ready-mixed fertilizer
such as 10-30-10 at 600 lb./acre. Fields - If available, apply manure at 10
tons/acre is spread and disked in during the spring months. Before
transplanting, broadcast and disc in the following: Nitrogen: 150-200 (N)
lb./acre. Apply remaining nitrogen as indicated below. Phosphate: 175-200 (P2
05) lb./acre Potash: 150-200 (K2 0) lb/acre Sulfur: 20-30 (S) lb/A Three weeks
after transplanting side-dress with 35-70 lb./acre of nitrogen. Apply another
side-dress as needed. When using calcium nitrate applied through irrigation,
limit nitrogen applications to 25-30 lbs./acre at any one time or excessively
fast growth will occur. This may result in cracking and related disorders. Fast
growth will also result in celery that will become pithy quickly, reducing
keeping qualities. If magnesium deficiency is likely to occur, apply Epsom
salts at 5 to 10 lb./acre when the plants are about one-third grown. When boron
is needed, broadcast boron at 1-2 lb./acre. A potassium excess or a boron -
potassium imbalance can cause "brown checking". A calcium imbalance or
deficiency can cause black heart. This occurs most frequently during periods of
moisture stress and rapid growth during periods of high temperature. If
temporary wilting occurs, irrigate, then spray (direct into the heart of the
plant) with 10 lbs calcium chloride or 15 lbs calcium nitrate per acre. If
moisture stress continues, reapply calcium chloride or calcium nitrate once per
week. Muck soils: Add lime to maintain a pH above 5.5 on muck soils. Transplant
Seed-beds - Broadcast and rotate in a ready-mixed fertilizer such as 10-30-10
at 600 lb./acre. Nitrogen: 100-150 (N) lb./acre. Apply additional nitrogen as
indicated below. Phosphate: 175-200 (P2 05) lb./acre Potash: 150-200 (K2 0)
lb/acre Sulfur: 20-30 (S) lb/A Three weeks after transplanting side-dress with
35-70 lb./acre of nitrogen. Apply another side-dress as needed. When using
calcium nitrate applied through irrigation, limit nitrogen applications to
25-30 lbs./acre at any one time, or excessively fast growth will occur. This
may result in cracking and related disorders. Fast growth will also result in
celery that will become pithy quickly, reducing keeping qualities. If magnesium
deficiency is likely to occur, apply Epsom salts at 20 lb./acre (2 lbs actual
magnesium) when the plants are about one-third grown. If deficiency persists
beyond 10 to 14 days, reapply 20 lbs Epsom salts per acre. Two applications
should be sufficient. When boron is needed, broadcast 10 lbs of borax per acre
(1 lb actual boron). A potassium excess or a boron - potassium imbalance can
cause "brown checking". A calcium imbalance or deficiency can cause black
heart. This occurs most frequently during periods of moisture stress and rapid
growth during periods of high temperature. If temporary wilting occurs,
irrigate, then spray (direct into the heart of the plant) with 10 lbs calcium
chloride or 15 lbs calcium nitrate per acre. If moisture stress continues,
reapply calcium chloride or calcium nitrate once per week.
Water Management
Celery requires a uniform supply of water. Frequent irrigation is
preferred. Soil type does not affect the amount of total water needed, but does
dictate frequency of water application. Lighter soils need more frequent water
applications, but less water applied per application.
Harvasting Handling and Storage
Celery may be hand harvested or machine harvested, but that which is grown
in Oregon is hand harvested. Harvest when stalks are of sufficient size but
before any pith has developed in the petioles. In some U.S. production areas,
celery is trimmed to produce "hearts" which are packaged 2 or 3 per package
with the stalks that are trimmed off being used for processing. It is critical
that harvested stalks be quickly cooled.
Storage
Celery at 32 F and 90-95% relative humidity. Celery should keep for 2 to 3
months if stored in rooms held uniformly at 32 F. However, less celery is
stored now than in former years. Since wilting is a major cause of
deterioration, it is best to store celery at very high relative humidity (98 to
100 %) and with sufficient air circulation to keep temperatures at the top and
bottom of the room as nearly equal as possible. Spreading burlap on the storage
room floor and keeping it constantly wet is one method of maintaining a high
relative humidity. The use of perforated polyethylene film crate or carton
liners also provides an effective method of maintaining high relative humidity
to minimize moisture loss. Prepackaging with shrink film sleeves or with
open-top plastic bags also is a good way to retain moisture without the danger
of accumulating carbon dioxide or depleting oxygen. Celery can be precooled by
refrigerated forced-air cooling, by hydrocooling, or by vacuum cooling.
Hydrocooling is the most common precooling method, and temperatures should be
brought at near to 32 F as possible. In practice, temperature reduction is
often only to 40 to 45 F. Vacuum cooling is widely used for celery packed in
corrugated cartons for long-distance shipment. Ice is often added to the crates
to keep the celery near 32 F. Air circulation can be maintained around crates
by using dunnage strips between the crates and leaving air channels between
rows. If wall or ceiling refrigerating coils is used, fans should be located so
that they will provide adequate air circulation. Celery should not be stacked
more than four crated high in storage without forced-air circulation;
otherwise, there is danger of overheating due to heat of respiration. For
better storage, celery should be cut with a small piece of root attached and
harvested before the outer stalks become pithy. Some growth takes place in
celery while in storage; the central stalks lengthen considerably. Some
blanching of the stalks also takes place in most cultivars during storage.
Celery is rather perishable, and under unsuitable storage conditions it is
especially subject to watery soft rot. This disease originates in the field and
is caused by a fungus that is able to develop to some extent even at 32 to 34
F. Use of the jacketed-room system for cold storage has proven successful for
celery in Canadian tests. Weight losses at 32 F averaged 1.25 %/month in
jacketed storage as compared with 2.5 %/month in directly cooled rooms. An
atmosphere containing 3 % oxygen and 5 % carbon dioxide reduced decay and loss
of green color in celery held at 32 F in high-humidity storage.
Packaging
Celery is packaged in 55-65 lb. crates and wire bound crates, or flat pack
containing 2 1/2 to 6 dozen bunches each. Celery hearts are packaged in 24-28
lb. cartons, holding 12 or 18 film bags, or 32-38 lb. wire bound cartons.
Disease and Pest Management
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
Proper cultivation, field selection and rotations can reduce or eliminate
the need for chemical weed control. Stale seedbeds are sometimes used for
vegetable production when other selective 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. 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. Plant the crop with minimum soil
disturbance. Otherwise, new weed seed will be exposed to favorable germinating
conditions. Just before or after planting but before crop emergence, treat the
field by flaming or with herbicide to kill all germinated or exposed weeds.
Disease Management
Proper rotations, field selection, sanitation, spacing, 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
reduce risk from seed born diseases. Some of the common diseases of celery and
their remedial measures are given below:
|
Name of Disease
|
Recommended Remedy
|
|
Black Heart
|
Spraying foliage with a water solution of calcium
nitrate at the rate of 15 lb of calcium nitrate/A.
|
|
Cracking
|
Applying from 1 to 5 lb of actual boron/A. Sandy soils
usually require a larger amount.
|
|
Early Blight
|
Treat seed with hot water for 30 minutes at an average
temperature of 105 F. Where seed is 3 to 4 years old, the fungus is no longer
viable and treatment is not necessary. Spray seedlings in hot frame or
greenhouse flats and also plants in the field with Bordeaux 8-8-100. Use a good
spreader-sticker at 1 or 2 oz/100 gal water with all materials. Make the first
field application when the plants have started growing and are well established
following transplanting. Later applications should go on at 10-day intervals. A
copper lime dust (20 percent copper, 80 percent lime) has been used in place of
Bordeaux. Remove all old celery refuse from the field and destroy it. Use Bravo
.75 to 2.25 lb actual/A. Note: `Emerson-Pascal' is tolerant to this disease.
|
|
Fusarium Yellows
|
Avoid introducing this disease by preventing the
movement of soil, water, or plants from infested areas. Never dispose of celery
trimmings on land that may grow celery. Once introduced, buildup of inoculum
can be reduced by rotating with unrelated crops such as corn, cole crops,
cucurbits, or onions. Grow resistant cultivars such as `Summit', `Vicar', and
`FL683'. In British Columbia, Deacon and T.U. 52-70HK are most resistant
followed by Tender crisp and Bishop.
|
|
Late Blight
|
Use tolerant varieties where practical. The variety
`Emerson-Pascal' is tolerant to the disease. Use seed at least 2 years old.
This fungus is introduced in plantings primarily through infected seed. The
fungus in the seed dies within 2 years and thus should be disease free after
that period. Treat seed with hot water for 30 minutes at 105 F. Often this
treatment will reduce seed germination. Plant in fields that have not had
celery for at least 1 year. Fungicide sprays: Apply every 14 days after the
plants are set out until the fall rains begin, then apply every 7 days. Use
Benlate, Bravo, is not being produced. Material that is available can be used
as labeled.
|
|
Northern Bacterial Blight
|
Obtain clean transplanting stock. Do not handle
transplants when they are wet. Avoid mechanical operations in the field that
can spread the bacteria, particularly when plants are wet with dew or
irrigation water. Spray the plants with a fixed copper to prevent spread. These
sprays are usually necessary only during cool, wet weather.
|
|
Sclerotinia Disease (Pink Rot)
|
No good control measure exists for this disease.
Rotation for 2 or more years to non-susceptible crops is helpful.
|
|
Soft Rot
|
Control in the field is almost impossible. Harvest
celery quickly and put in cold storage promptly in order to reduce postharvest
losses.
|