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17 - Kale

Brassica oleracea
Varieties
  • Red Russian
Growing Conditions
Cold Tolerant
Disease and Pest Notes

Adhere strictly to a preventive program including: (1) long crop rotations with non-brassica crops, (2) clean starting mixes and outdoor seedbeds, and (3) strict sanitation practices.

Kale is not as afflicted with pests as are other brassica crops such as cabbage. Apply row covers at the time of planting to exclude pests from the crop. Control cabbage worms and loopers with Bacillus thuringiensis (Bt).

Mulch Type
Wood chips after planting
Propagation
Seed
Life cycle
Soil block size
3/4 in to transplant. Or 1 1/2 soil blocks
Seed germination temperature
Low 40 - Optimal 75 then reduce air temp to 60
Heat mat temp
75°F (24°C)
Cool germination details
75 then air temperature to about 60°F if possible. Cool area.
Culture and fertilization requirements

Kale prefers a fertile, well-drained soil high in organic matter with a pH range of 6.0–7.5. Consistent moisture will produce the highest-quality leaves. For baby-leaf production, see the Baby Leaf Brassica Greens culture.

Kale prefers cooler growing temperatures, between 55–75°F (13–24°C), optimum being 60–70°F (16–21°C), but will produce good crops under warmer, summer conditions. Successful kale crops can be grown where winters are mild and temperatures rarely fall below 32°F (0°C). Transplants can be set out from September to February in these regions.

Succession interval - maximum
2 weeks
Harvesting details

Beginning about 2 months after planting, harvest by clipping individual leaves. Kale is very hardy, and the eating quality will improve into the late fall with light frost. Late-summer sown or planted collards can be wintered in cold frames or hoophouses, or in the open in mild regions, to extend the season. Protecting with row covers can extend the harvest period.

Kale tastes best when plants grow rapidly and mature before the heat of summer (before temperatures exceed 75°F/24°C) or after fall frosts occur. Young plants are not seriously damaged by temperatures down to 25°F/-4°C. Mature plants are extremely hardy and can withstand very cold temperatures. However, hot temperatures will slow growth and cause bitter flavor.

Current Seed Start & Transplant Dates

Note: Seed starting and transplant dates do not always correlate one to one with dates shown below. Note correct start and expected transplant dates on the tag of the tray for seed germination. Adjust dates with plant tags on a yearly basis if necessary. 8 ounces of fertilizer is about 1 cup. Consider Sustane various NPK and Alfalfa Meal or Blood Meal for nitrogen.

Seed Start to Transplant Days 28 - 42 days
Days to Maturity after Transplant 21
Days to Maturity Total 29 baby; 50 full size
Spring Expected Harvest Date Range 04/01 to 06/01
Athens
Franklin


Transplant Details: 12"

Direct Sow Dates ( if any )

Seed Viability Years
3 - 5 years

Variety Details

Variety Name
Red Russian
Variety Description
Smooth, green, purple-veined leaves for baby leaf and bunching. Stems are purple; leaves are flat and toothed with purple veins. Mature plants are medium-tall and leaves are tender compared to other kales. For salads and light cooking.
Seed Type
Open Pollinated
Seed Vendors
Johnny's 100 / $5.15