Siberian Improved

Family: Brassicaceae Vegetable

Cool-weather vigor meets richly satisfying flavor in Siberian Improved kale.

Expect deep, blue-green leaves with a tender, slightly sweet bite that softens beautifully as temperatures dip, making it a standout for hearty greens from the garden. Grow it for reliable harvests around day 50—ideal for steaming, sautéing, and robust sauces, or for pickling when you want a tangy, long-keeping green.

Light: Full SunMaturity: 50 DaysHabit: Rosette

Botanical illustration of Siberian Improved

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Mar 28th
Last Frost	Apr 25th
Transplant / Sow Outdoors	Apr 18th
Harvest Begins	Jun 7th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	50
Sun Requirements	Full Sun
Growth Habit	Rosette
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	45
Min Soil Temp (°F)	40
Min Night Temp (°F)	30
Harden Off (days)	6

Culinary Notes

Chef's Note

Siberian Improved is the kind of kale that stays pleasant even when the temperature drops—sweetness arrives as the leaves soften, not just heat-sick bitterness. Treat it like a braising green: salt early, cook until glossy, then sharpen with lemon or vinegar so the brassica bite feels bright instead of harsh.

Best Uses

quick steam or sauté, then finish with a splash of lemon for a sweet-bitter pop
braise in a salty broth until the stems go tender and the leaves go glossy
blend into a thick, creamy green sauce for pasta or dumplings (use starchy water to emulsify)
pickling for tangy, long-keeping greens that stay pleasantly crunchy

Flavor Profile

deep blue-green bitterness with a clean, slightly sweet bite tender leaf that turns silkier with cool-weather cooking toasty, mineral brassica character holds structure for braising before going silky at the edges

Kitchen Pairings

lemon olive oil parmesan white beans smoked pork red pepper flakes

Frequently Asked Questions

What pest or disease is most likely on Brassica oleracea (true Siberian types), and how do I manage it at home?

Watch for cabbage worms (imported cabbageworm/diamondback) and aphids, which commonly attack Brassica oleracea foliage, especially in warm spells. Hand-pick caterpillars when you see them and spray an approved Bt (Bacillus thuringiensis) product at first sign of chewing; for aphids, blast with water and repeat every 2–3 days until colonies crash. If you notice yellowing with whitish mildew-like patches or persistent leaf spotting, remove badly affected leaves promptly and avoid overhead watering to slow spread.

How often should I water Brassica oleracea during the main growing phase to prevent stress and bolting?

During active leaf growth, keep the soil consistently evenly moist—aim for watering when the top 1 inch of soil feels dry. In full sun, this usually means about 1 inch of water per week total (more in hot, windy periods), delivered in deep soakings rather than frequent light sprinkles. Avoid letting plants swing between dry and wet, which can trigger bitterness and can contribute to early bolting.

How can I tell when my Brassica oleracea (true Siberian, ~50 days) is ready to harvest?

Harvest when heads/foliage reach their expected size for your planting and leaves feel firm rather than floppy, typically around 50 days from sowing (or about the time the plants stop rapid expansion). For leaf-harvest types, pick outer leaves first when they’re fully expanded and tender, and stop once the center starts to elongate. If you see the plant turning upward with a stem forming, harvest immediately—once flowering begins, flavor quality drops.