How to grow beautiful cauliflower

Top tips for growing cauliflower:

• plant seedlings deeply
• space according to instructions
• install dripline
• keep well watered

Cauliflower is sometimes avoided by gardeners because of poor results but it is very easy to grow large, beautiful, compact, snowy headed plants.

The cauliflower head is the flower and it consists of unopened curds or florets which should be tight and white. When they are loose and yellow, they are quite unappealing and disappointing. Yellowing and lumpiness are caused by exposure to strong sunlight. To avoid this, tie the inner leaves over the cauliflower head. Some varieties called ‘protecting’ or ‘self blanching’ will naturally do this but some will need your intervention. Don’t worry if the leaf breaks. It will still do its job. This process will also protect the heads from frosts.

There are 2 reasons that cauliflowers develop small heads. The first is caused by hot weather – they are, after all, a winter crop requiring cold soil and air. The second is wobbly stems which are, in turn, caused by seedlings not being planted deeply enough in the soil. As the wind blows the stem from side to side, the plant loses traction in the ground and the roots become loose and don’t do their job.

Planting cauliflower

Plant seedlings (also seedlings of broccoli and cabbage) so that their base leaves are covered in soil. If you find that your stem is too high then dig it out and plant it deeper or if you notice this at a later stage, then hill the soil up the stem so that it covers the base leaves. In fact it would be difficult to plant a cauliflower too deeply. If the top leaves are exposed, it will grow well. The stem will not rot which seems to be many people’s concern. You could also hill the plants in the first place, a practice that was normal for both my grandfathers, and one with which I have had success.

Soil preparation for cauliflower

For next season, prepare your garden beds, by forking over your soil in autumn to break up the surface crust, aerate it, and allow moisture to penetrate. It is vital that you spend time watering and moistening your soil which is likely to be quite dry after summer. Make sure your site is well drained however as water logged soil will lead to disaster. Remove any stones, sticks and break up clods and then dig in lots of compost and low nitrogen manure. (High nitrogen manure such as chicken or fish leads to leaf development at the expense of cauliflower heads.)

The soil pH should be 6.5 – 7.5. Lower than 6.5 results in deformities such as whiptail and clubroot that cannot be later remedied. If your soil is acidic it may need lime or dolomite but test first. If you do need to add one of these, your preparation time will be extended as liming needs to happen a month before the addition of manure or it ties up the nutrients in the manure.

For good heads, regular watering is essential throughout the winter, and mulching is important for weed suppression and moisture retention. As leaves are large, they can obscure the soil surface making watering difficult and blocking rain from reaching it. The soil can be surprisingly dry, even in wet weather. To remedy this, install dripline and turn it on at least twice a week for several hours.

Written by Robin Gale-Baker. First published in the Local Food Connect newsletter. Updated March 2021.