Growing and The Timing For Blanching Cauliflower For The Biggest, Whitest Heads

Growing cauliflower is easy.

It's a simple plant to start but some gardeners get confused about blanching the curds (white heads).

Variety Selection

It is all about attention to detail and variety selection.

Sow seed around the beginning of March for a May transplanting to the outdoors (8 weeks before you want to put it into the garden)

basil citriodora boxwood


Planting Cauliflower

Plant seeds approximately one quarter inch deep and germinate around 70F. It should only take 7 days for seeds to germinate and some will be up in 5. Once the seeds have germinated, grow them cooler (60-65F) but no colder because if the seedlings get too cold (50F) they'll wind up bolting (going to flower) in the field instead of setting a head.

Harden off the fast growing cauliflower transplants and set outside after danger of frost has passed. While the plants themselves can take frost, the cool nights will cause them to bolt later on (see above) Transplants should be put 18 inches apart in the row and rows should be 30 inches apart.

You can direct sow cauliflower seed outside after the middle of May right up to the middle of June and still get a good fall crop. Again, the seeds go down one quarter inch deep and about three seeds to the foot (you'll thin them out and use the thinnings as transplants).


When it comes to thinning in about five weeks, you'll want to choose the thinnest and straightest plants. Throw away any seedling that looks like it is swelling (and trying to set a head already). Thin to one strong growing cauliflower plant every 18 inches.

Here's the part that folks don't seem to get right.

Book cover Vegetable Gardening


When the growing cauliflower head (called a curd) is about the size of a coffee cup (tea cup) take the big outer leaves and tie them up over top of the curd. Use rubber bands to keep the leaves firmly over the curd so that no light can get into the middle of the plant.

This is why by the way that you need to control cabbage worms as they eat holes in the darned leaves that let light through. If the leaves are too small or too holey – you can use a paper bag over the curd (not our first choice but it works.)

Note that if you let the growing cauliflower curd get too big, it simply won't turn back to clear white (more like ugly cream) or stay yellow. It is still edible just ugly.

Blanching will only take a few days – ten at most and the head can be harvested. The warmer the weather, the quicker the curd will turn white (3 to 4 days if it is really hot).

Control the major pest of cauliflower, cabbage butterfly, using organic methods such as Bt.

Shopping Resources for this Page

Vegetable seeds and plants from multiple suppliers can be found here for all your vegetable gardening needs

You can find all of Doug's ebooks here

Want A Stunning Garden? Click Here For Your Free Lessons