Brassica oleracea var. medullosa
Marrow-stem kale
Common names: Marrow kale, Cow cabbage
At a glance
- Light
- Partial shade
- Spacing
- 60 cm, rows 70 cm
- Lifespan
- Biennial
- Sowing
- Apr–May
- Harvest
- Oct–Dec
- Hardiness
- Hardy down to −8 °C
- Water need
- Medium
Photo: Goldlocki · CC BY-SA 3.0 · Source
Description
Marrow-stem kale is an old, almost forgotten field garden cabbage with a thick, fleshy stem that can grow up to two meters tall. Traditionally it was used as livestock feed, but the young leaves and tender stem core taste mild and cabbage-like when cooked, a robust piece of garden history.
Care instructions
From May onward give it a sunny, nutrient-rich location and plenty of space, as it will grow tall and sprawling. Slightly mound the lower stem and support the plant in wind so it does not topple. Harvest the leaves continuously and the core in late autumn when the stem has reached its full thickness.
The care notes were machine-translated from German.
Garden year
SowingApr–May
HarvestOct–Dec
Germination
- Soil temperature
- from 5 °C, ideally 20 °C
- Days to sprout
- 4 to 10 days
- Light
- Sprouts in light or dark
- Sowing depth
- 1 cm
- How to start
- Sow straight into the bed
Soil & site
Soil pH
Soil type
loamy, humus-rich, nutrient-rich, well-drained
Marrow-stem kale needs a deep, nutrient-rich and evenly moist soil. Loamy-humus soils with good water-holding capacity are ideal; pure sandy soils dry out too quickly, and it does not tolerate waterlogging and compaction. Before planting, work in ripe compost generously. On acidic soils a little garden lime helps: it raises the pH and prevents clubroot, which is particularly active in acid conditions. It is tolerant of location: it grows equally well in sun to partial shade.
Brassicas are heavy feeders and susceptible to clubroot. Keep a 4-year break and do not follow directly after other brassicas such as radishes or mustard.
Feeding
Heavy feeder
Months
Mar–Jun
In spring before planting, work ripe compost shallowly into the soil. At planting time, add horn shavings or horn meal to meet the high nitrogen requirement organically. About three to four weeks after planting comes a second helping of horn shavings around the plants, worked in at the surface and watered in. Do not put fresh farmyard manure directly at the roots; only well-matured compost.
Overwintering
Marrow-stem kale is hardy and stays in the bed without protection. Frost even makes it milder, similar to kale, and you can harvest the leaves continuously over winter. In the second year it grows again and flowers; if you want to keep getting leaves, cut out the flower buds.
Propagation
Methods
- From seed
You propagate marrow-stem kale exclusively by sowing. Vegetative methods are not practical for this biennial Brassica species. (Note: cutting tips circulating in the trade refer to the perennial “tree kale”, a different variety, not to marrow-stem kale.) For starting indoors, sow the seeds from March in pots or trays about 0.5 to 1 cm deep at about 18 °C on the windowsill. As soon as the seedlings are strong enough, prick them out into individual pots and from mid-April gradually put them outside to harden off. Direct sowing outdoors works from April into June, in mild weather even before the Ice Saints (mid-May): sowing depth likewise 0.5 to 1 cm, row spacing about 50 cm. Strong seedlings you thin to about 30 × 50 cm spacing. The seeds germinate in about 8 to 12 days at 10 to 20 °C; keep the seedbed evenly moist. If you want to save your own seed, let selected plants flower in the second year. The yellow flowers are pollinated by bees and form pods. Harvest the seed as soon as the pods are brown and dry, and store it cool and dry for the next season. Marrow-stem kale is open-pollinated (not an F1 hybrid), so it stays true to type.
Companion planting
Good neighbors
legume family (Fabaceae)
particularly well establishedLeguminous plants collect nitrogen in the soil, from which Brassicaceae benefit as heavy feeders.
For example Bush beanPole beanBroad beanSnow peaWrinkled peaRunner bean and 35 more species in the catalogue
Source: classic companion planting (DACH-Gartenpraxis)
carrot family (Apiaceae)
You can pair celery and dill with all Brassicaceae because they repel the cabbage whitefly with their scent, a proven companion.
For example CarrotCeleriacDillParsleyFlorence fennelCoriander and 21 more species in the catalogue
Source: Bio-Gärtnerei Mixed-culture Practice
mint family (Lamiaceae)
You will notice that the intense scent of basil, thyme, and others confuses the cabbage whitefly and keeps it away from the cabbage family.
For example LavenderThymeBasilRosemarySageHyssop and 43 more species in the catalogue
Source: bio-gardening intercropping practice
nasturtium family (Tropaeolaceae)
Nasturtium serves as a trap plant for you. Aphids and cabbage whiteflies prefer it over the brassicaceae next to it.
For example NasturtiumMashua
Source: Trap plant practice in organic horticulture
Rather not
Companion planting is partly traditional gardening lore. Where the reason is known, it is given.
Some of these explanations were machine-translated.
For signed-in gardeners
Sign in to see symptoms, severity, season and prevention for every one of your plants.
Free account, set up in 30 seconds.
For your garden
Grow Marrow-stem kale yourself
Gartenkern tells you when frost is coming, when to sow and when to harvest, for your location.
Free, no time limit
Notes from real gardens
What other gardeners have written down about this variety, anonymous and voluntary.
No notes shared yet. Will you be the first to write one down?