Vegetable Seed Production: Celery

You are here: Seed Production: Apiaceae: Celery

Common Name: Celery Scientific Name: Apium graveolens Family: Apiaceae

In addition to reading the information in this section, please view this video on Celery Seed Production (The video will open in a new window.)

Botany

Family Apiaceae (Umbelliferae is the old name.), Apium graveolens. Celery is a cool season biennial that is grown as an annual.

Hardened plants can briefly withstand temperatures a few degrees below freezing.

The plant is easily vernalized by exposure to temperatures less than 50 degrees F after it has developed passed the juvenile phase.

The vernalized plant quickly produces a flower stalk (bolts) that inhibits further stalk development.

Unless the crop is being grown for seed, bolting (flowering) ruins the economic value of the crop and must be avoided.

During the first year of growth, celery forms, a short subconical stem bearing a spiral rosette of leaves on the end of an elongated petiole.

Generally, the petiole is the most important edible portion.

The petiole is cresentric in transection with prominent ribbing on the abaxial (inside) surface and a relatively smooth adaxial (outside) surface.

The ribbing is a result of bundles of collenchyma on the abaxial side. The collenchyma bundles along with the vascular bundles that run through the center of the stalk are responsible for the stringiness of celery. Botanist Katherine Esau demonstrated that the collenchyma is mechanically a very strong tissue, being about four times as strong as the vascular tissue.

Soil Nutrition

• Celery prefers a soil pH of about 6.5 on mineral soils and about 5.8 on organic soils
• Celery crops produce a large biomass and therefore is one of the heaviest feeding vegetable crops
• Little biomass is produced during the first month after transplanting and the greatest nutrient requirements occur the last 4 to 6 weeks before harvest. Therefore, split applications of fertilizer are applied
• A side dressing of N and K is commonly applied 6 to 8 weeks before harvest
• Celery can remove approximately 275 lbs/acre N, 55 lbs/acre phosphate, and 300 lbs/acre of K
• Calcium is important for cell wall formation and calcium deficiency can cause a physiological disorder called black heart, which results in the death of the apical meristem in the heart of the plant
• Celery is sensitive to boron deficiency which may result in lateral cracking across the petioles

Isolation

Because of the high possibility of cross-pollination, isolation distances for commercial seed crops should be a minimum of 800 m. For basic seed the distance should be greater, about 1600 m.

Planting

Celery seeds are very small, slow to germinate, and emergence is very irregular. Therefore, celery is always field planted using 4 to 6 week old transplants. Plug tray transplants are most commonly used.

Irrigation

• Uniform soil moisture is essential
• Water stress will slow growth and decrease yields
• Studies show that replacing 100% of evaporative losses results in the highest yields
• One inch of water per week or 10 days is also a standard recommendation
• Water is needed most at the time of expansive growth of the leaf tissue
• In western states, overhead irrigation may be used to establish the crop and activate fertilizer and furrow irrigation is used after establishment until just before harvest
• In eastern states, overhead irrigation is used throughout the entire season

Roguing

Celery roguing, stages and characters to check

1. Planting out: Leaf and petiole characters, plant vigor

2. Vegetative stage in field
(a) Early bolters should be rogued out
(b) Leaf and petiole characters
(c) Leaf color, size, length, color of leaf tip
(d) Petioles
(e) Length
(f) Color - light to dark green, yellow, white or pink

3. Lifted plants
(a) Absence of basal shoots
(b) Width of heart (solidity of plant)
(c) Susceptibility to bolting

4. Second year (before flowering)
(a) Susceptibility to Septoria apiicola Speg. and other seed-borne pathogens
(b) General plant vigor. For basic seed production, special attention should be given to petiole characters, such as width (transverse section), petiole ribbing and general petiole characters including pithiness

Seed Harvest

The seed crop is ready for harvesting when the plants show signs of senility and the majority of seeds on the major inflorescenses have become a gray brown color

Celery seed is notorious for shattering prior to harvest even in the best of conditions and a lot of valuable seed can be lost if bad weather occurs or the cutting time is misjudged.

When produced in tunnels or relatively small areas outside, the plants can be pulled or carefully cut and placed on tarpaulins. In large-scale production the crop is carefully cut, dried in windrows and combined before excessive shattering has occurred.

Cleaning

If a combine is not used the material can be passed through a stationary thresher, but if dried on tarpaulins, especially under cover, the seed separates from the straw without machine threshing. Seed is further cleaned by an aspirated screen separator, but because the seed is very small, care must be taken in selection of the bottom screen.

Seed Yield

The average seed yield is about 500 kg per hectare (446 lbs/acre). Seed weight: the 1000 grain weight of celery seed is approximately 0.5 g.

Seed Identification: