Collards Growing Guide
|Soil Temp for Germ.||Days to Emergence||Seed Depth||Thin Plants To||Seed Spacing||Row Spacing||Min. Germ.||Seed Life||Seeds per gram||Fertilizer Needs|
|55-75°F||5-17||1/4"||12-24"||1-3"||18-36"||80%||3 years||≈ 250||Medium|
Brassica oleracea, Acephala Group Collards are among the best vegetable sources of vitamin K. This nutrient is said to limit neuronal damage in the brain, aiding in the prevention, or delaying onset of Alzheimer's disease.
Days to maturity are calculated from date of transplant.
• Collards are a cool-season crop that performs best in spring and fall
• In wet climates, ensure adequate plant spacing to reduce pest and disease issues
• Cover seed with loose soil, vermiculite, or sifted compost and water evenly
• Sow June—July for a fall crop
• Start indoors 4-6 weeks before anticipated transplant date
• Work in 1/2 cup of TSC's Complete fertilizer around each plant
• Start May—July for transplanting June—August for a fall crop
Insects & Diseases
• Common insects: See Brassica Insect Information below
• Common diseases: Leaf spot, black rot, fungal diseases, mold, mildew, club root
• Disease prevention: Dispose of diseased material, proper crop rotation of 3-4 years, apply Zonix for mildews
Harvest & Storage
• Harvest leaves from the bottom up at any size
• Cool weather and frost brings out best flavor
• Store at 36°F and 95% relative humidity
Brassica Insect Information
Aphids: Control aphids with ladybugs or a hard spray of water or Pyrethrin. Also, select varieties that mature later in the season when aphid populations decline.
Cabbage worms, loopers, and root maggots: The first sign of cabbage worms will be off-white butterflies fluttering near the plants. They lay their yellowish-colored eggs on the undersides of leaves, which hatch into caterpillars that can cause severe root and head damage. To control light infestations, spray plants with Bacillus thuringiensis (B.t.). For heavy infestations, bait cabbage worms by mixing wheat bran into a B.t. solution. Add 1 tablespoon of molasses. Broadcast the bran mixture around the base of plants. Reapply as necessary. Using Reemay or Summer Insect Barrier can also provide control.
Flea beetles: Flea beetles chew tiny pinholes in leaves. Early control is essential to minimize the damage. Spray infected plants with Pyrethrin. Using floating row covers such as Summer Insect Barrier can also provide control.
Symphylans: In some areas of the US, symphylans (also known as garden centipede) can severely impede the plant growth of many crops. Only 1/4 inch long, white, and very active, they eat the root hairs of developing plants. Using larger transplants helps reduce damage. Contact your local county extension agent if you suspect you have a problem.