Sow brassicas like kale and cauliflower indoors now for productive, tasty crops – 6 types to start in February

Brassicas are roast dinner essentials – Brussels sprouts, cabbage, and kale, to name a few. For enhanced flavour, you can grow your own – and there are plenty of brassicas you can sow indoors in February to get a head start.

There’s no shortage of fruit, vegetables and flowers you can sow in February, but if you’re growing them from seed, you’ll need to start most of them off indoors at this time of the year. Of course, if indoor growing space is limited, there are a fair few vegetables you can plant under cloches outside this month – but many brassicas benefit from indoor sowing while it’s still cold outside.

So, will it be hearty cauliflower or nutrient-packed kale? Here’s a list of brassicas to sow indoors on a windowsill, in a propagator or in a greenhouse this February.

1. Kale

Learning how to grow kale is a breeze. It almost feels too good to be true that it’s so easy to grow your own superfood at home – but even beginner gardeners can master it.

‘Kale is absolutely the most reliable brassica you can grow,’ agrees YouTube sensation and grow-your-own expert, Huw Richards, who has partnered with watering and hand tools brand, GARDENA. ‘Curly kale and early cropping types are ideal for February sowing, as they’re fast to establish and very forgiving.'

If you’ll be sowing these brassicas indoors in February, Huw recommends planting the seeds in modules rather than trays to minimise root disturbance and keep growth moving steadily. These seed trays with cells from Amazon are ideal, and they even come with a lid.

‘Keep seedlings in strong light, on the cool side, and harden them off gradually before planting out, only moving them outside once conditions are right,’ he adds.

The days are still quite short here in the UK, but grow lights like these from Amazon can be a brilliant supplement for natural daylight.

2. Cabbages

Cabbages featured in Pinterest Predicts for 2026, and B&Q thinks they’re going to be popular alongside a renewed interest in picking and fermenting food this year. They’re a shining example of brassicas you can sow indoors in February, too – and an early start is wise.

‘One of the most common mistakes is sowing too late, which can result in smaller heads or plants struggling in colder weather,’ explains B&Q’s horticulture expert, Mark Sage. ‘Starting now can give cabbages time to establish strong roots.’

If you’re keen to sow cabbages outdoors, Mark says April is the ideal window – but there’s nothing stopping you from raising young plants indoors now, ready to be transplanted into the garden in spring.

‘For February sowing, I tend to favour spring cabbages or early pointed types, which establish quickly and are well suited to cooler conditions,’ adds Huw. Cabbage 'April' is a popular spring variety – you can buy the seeds from Amazon.

3. Cauliflowers

Cauliflowers are slightly trickier to grow, but that makes them all the more rewarding. They’re suitable for sowing indoors in February, but they’ll need some extra care if you want them to grow into strong plants.

The key, Huw says, is to treat cauliflowers well from day one – that’s the surest way to grow tight, high-quality heads.

‘Early or summer cauliflower varieties are best suited to a February sowing indoors, as they’re bred to crop reliably from an early start,’ says Huw. ‘Avoid any checks in growth caused by cold, drought, or root disturbance, as this is what leads to small or premature curds.’

Cauliflowers also appreciate a rich, moisture-retentive soil, according to Huw, ‘As they’re heavy feeders and don’t cope well with poor fertility.’

This Miracle-Gro Peat Free Premium Moisture Control Compost from Amazon takes the guesswork out of watering by storing and releasing water when plants need it. A few companion planting ideas can keep pests at bay once the plants are moved outside, too.

4. Brussels sprouts

Sprouts aren’t just for Christmas – they’re a feature of roasts throughout the year in many households. If you do want them ready in time for Christmas, though, you can get started by sowing the seeds indoors in February.

‘Brussels sprouts can be sown early,’ confirm the plant doctors at online garden nursery Crocus. ‘Just keep seedlings cool and well lit to stop them getting leggy, and harden them off gradually before planting outside.’

Crocus has a brilliant range of heirloom and modern pest and disease-resistant brassica seeds to choose from.

Sprouts have benefits beyond the kitchen, too: you can use the leaves to deter slugs, for example.

5. Broccoli

Broccoli is a slow-growing vegetable that’s known to grow in winter, but because it has such a long growing season, you can start sowing the seeds indoors now.

‘You can sow brassicas such as broccoli and calabrese now, using seed trays or modules in a bright, frost-free spot, at a temperature of around 10-12°C,’ say Crocus’ plant doctors.

Sow Broccoli 'Claret' F1 (purple sprouting) seeds from Crocus for delicious purple spears.

6. Romanesco

Okay: romanesco is a type of cauliflower, and we’ve already covered those – but it’s always been a vegetable that fascinates me, and I thought it deserved its own place on this list.

There are unusual fruits, and then there are unique vegetables – and romanesco produces vivid-green, geometric florets with a sweet, nutty flavour.

When I first started my raised vegetable bed, my romanesco was obliterated by cabbage white caterpillars – and the same fate could befall many of the other brassicas on this list once they’ve eventually planted outside. That’s why it’s wise to stock up on butterfly netting like this from Amazon, which prevents butterflies from laying their eggs on your crops.

These Mr Fothergill's Cauliflower Romanesco Natalino seeds are highly rated on Amazon.

Brassicas are staples in the kitchen, and they taste even better when they're home-grown.