Sea kale, or Crambe maritima, comes as quite a surprise: both in the garden and in the vegetable patch, it’ll trigger questions by curious onlookers!
Sea kale, a summary
Botanical name – Crambe maritima
Common name – Sea kale
Family – Cruciferae, Brassicaceae
Type – perennial
Bearing – clump
Height – 12 to to 28 inches (30 to 70 cm)
Planting density – 4 to 6 plants per sq. yard (m²)
Exposure – full sun
Soil – any type, cool
Flowering – May to July
This plant’s name comes from the shape of its gray-green leaves. After all, they’re wavy and frizzled, just like those of regular kale. At the beginning of summer, cute and fragrant white flowers appear.
Planting sea kale
Whether you’re planning a flower bed or a vegetable patch, sea kale will for sure find a place in your garden. Even more so if you’re on the coast! Soil type has no influence on how your Crambe maritima will grow. In particular, salt in the soil isn’t even a problem. However, to truly thrive, Crambe requires:
- deep tilling between 12 to 16 inches (30 to 40 cm)
- as well as soil mix or ripe compost, both upon planting and as a regular topdressing,
- and sun.
For the planting, simply purchase young seedlings in stores and transplant them. Naturally, sowing is a great option as well. So as to start them off well, plant from March to June in seed holes 2 feet (60 cm) apart with 2 or 3 seeds per hole. After about a month, select the most vigorous sprout and thin the others away.
- Like all cabbages, sea kale sprouts are vulnerable to damping off.
Sea kale care
Undoubtedly, sea kale or Crambe maritima is a quixotic vegetable. On the one hand, it’s a striking ornamental plant and on the other hand it’s perfectly edible. Caring for it is straightforward and it’s particularly happy along the coast. Crambe doesn’t require anything specific in terms of care:
- in Fall, cut the clump back to ground level
- every Spring, topdress with ripe compost or manure , as ripe as possible to avoid any kind of root rot
- in case of severe dry spell, keep an eye on soil moisture and, if necessary, water.
Propagating sea kale
You can multiply your Crambe maritima in Spring by preparing root cuttings:
- unearth a mature clump (over 3 years old)
- segregate the largest roots from the rest
- chop them into segments that are around 4 inches long (10 cm); the important consideration here is that there should be at least 1 or 2 buds on each
- plant them in pots and wait for them to start sprouting again before transplanting them back to the ground.
Harvesting Crambe maritima
If you wish to eat your sea kale, here are a few important tips:
- You should only harvest after three year’s worth of growing.
- To make leaves edible, you’ve got to blanch them.
This means to keep them in the dark while still on the plant, so that they don’t see any sun at all (or only very little). With this in mind, just flip an empty pot over the center of the clump to cover the leaves. Every day, for one or two hours at dawn or dusk, remove the pot so that the plant can breathe. This also prevents molds.
- You can start harvesting the leaves after 3 to 5 weeks.
Sea kale has a somewhat nutty taste. Unlike the oysterleaf herb which also grows near salt water bodies, it doesn’t taste as salty.
Keeping and storing sea kale
In order for your harvest to keep, place it in the refrigerator. It’s also possible to freeze leaves, but first you’ve got to blanch the leaves in boiling water. Blanching is a term used in cooking, too! It is a partial cooking that makes keeping easier.
Diseases that affect Crambe maritima
Like most other Brassicaceae cabbages, Crambe is vulnerable to cabbage clubroot which is a fungal disease due to Plasmodiophora brassicae. Main symptoms are:
- wilting and/or reddening of leaves
- misshapen roots to the point of showing galls
If you realize that a plant is infected, it must immediately be removed and eliminated. Furthermore, to fully eliminate the disease, brace in for the long haul since you have to wait seven years before planting any type of Brassica on that same plot. As for pests that may damage sea kale, you’ll likely encounter:
- those frustrating slugs and snails
- large white, commonly called cabbage moth.
This double-purpose plant is ideal to decorate a garden, a terrace, and even a kitchen windowsill, since sea kale is also perfectly edible!
Sea kale on social media
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Sea kale clump by Steve Law under © CC BY-SA 2.0
Cluster of flowers by Phil Sellens ☆ under © CC BY 2.0
View from below by Nick Saltmarsh under © CC BY 2.0
Young sea kale leaves (also on social media) by Tuulemeelne ★ under Pixabay license