A member of the Brassica family, cauliflower is packed with vitamin C. Though the white “curd” of the cauliflower is most typically consumed, its leaves and stems are also edible. Cauliflower has emerged as a versatile replacement veggie, forming pizza crusts, bagels, and rice.
To help ensure your Cauliflower thrives, we’ve put together this how-to video and transcript, making it easy for you to succeed. :)
We’ll cover everything you need to go from seed to harvest and every step in-between. Covering topics like:
Glossary of Cauliflower terms
Varieties of Cauliflower available
Starting your Cauliflower seeds
Caring for Cauliflower at all stages
Fertilizer and/or Mulching
Transplanting best practices
Companion Plants do’s and don’ts
Common challenges and Their Solutions
Pests, Diseases and what to do about them
Harvesting and storing your Cauliflower
Glossary of cauliflower terms
Before we get started, let’s learn a little bit about cauliflower.
A process that provides shade in order to prevent the head from becoming yellowish green with an abnormal flavor. You can do this by gathering the longest leaves and tying them together over the white cauliflower head. Only the white varieties should be blanched though, as the more colorful ones need sunlight to develop their color.
The process of getting indoor seedlings used to outdoor conditions – like sunlight, varying temperatures, and wind.
A plant that’s able to pollinate itself, and can also get pollinated by wind, insects or by human hand.
The process of gently pulling out seedlings to leave only the strongest and most mature plants behind.
This encourages proper plant growth and allows your cauliflower to thrive without any major competition for water and nutrients. The removed plants (thinnings) can sometimes be transplanted to other spots in your garden.
The first leaves that look like those of a mature cauliflower plant - not the very first leaves to appear. These true leaves have sharper edges and are thicker than the seedling leaves.
Varieties of cauliflower
Did you know that cauliflower comes in a few different colors? It’s true.
WHITE (SNOWBALL, SNOW CROWN, SKYWALKER, MARDI)
This variety has the more widely-known white heads along with big leaves to wrap around for blanching.
GREEN (I.E. VITAVERDE, VERDI)
This variety has big green heads that mature early.
Similar Varieties: Broccoflower (Veronica, Puntoverde) A hybrid between broccoli and cauliflower, these varieties are greenish with geometric florets.
Cauliflower with a purple head that usually loses its color during cooking.
ORANGE (CHEDDAR, FLAME STAR)
Varieties with yellow to orange flower heads, which become even more intense in color when cooked.
A variety that’s bred to have long narrow stems with small white florets on the top. This variety is sweeter than regular cauliflower and has a crunchy texture.
Starting your cauliflower seeds
In order to germinate, seedlings prefer a soil temperature that’s between 50-85°F (10-29°C), though they can germinate at soil temperatures as low as 40°F (4°C).
Make sure to provide direct sunlight when your seedlings start growing, otherwise the plants can get leggy (when stems are too long and scraggly). In general, seedlings need about 14 hours of light each day.
Cauliflower seeds will also need about 4-6 weeks to grow to their transplanting size. Once they’re ready, you can set your transplants into your garden. Keep them 15-24 inches (38-61 cm) apart in rows that are 2-3 feet (61-91 cm) apart.
You can also start your seeds directly outside once the temperatures are reliably staying above 50°F (10°C).
Plant your seeds a half to three-quarters of an inch (1.2-1.9 cm) deep and spaced about 3 inches (7.6cm) apart.
Once they have 3-4 true leaves, you can thin them to be 12-18 inches (30-45cm) apart.
In general, cauliflower seedlings need about 14 hours of light each day.
Caring for cauliflower
In this section, we’ll cover everything you need to know about ideal growing conditions, fertilizer and mulch best practices, and transplanting. We’ll also cover companion planting as well as your growing structure options.
Cauliflower can be successfully grown in USDA zones 3 through 10. They prefer soils that have a pH between 6.0-7.5, and they also need consistent and sufficient soil moisture. Full sun is best for them to grow, but cauliflower can also tolerate some light shade.
They prefer air temperatures between 68-77°F (20-25°C) and grow best when temperatures do not go above 75°F (24°C). In hot and dry weather, typically their edible heads won’t develop. Keep in mind that delayed spring plantings can often expose your cauliflower plants to these hot temperatures.
Also, any disruption by extreme cold can also negatively affect their heads since cauliflower is more sensitive to cold than other cabbage family members.
To preserve the white head of your cauliflower, secure the leaves with a rubber band or string around the head when it’s about 3 inches (7.6cm) in diameter - about the size of a hen’s egg.
It protects the white portion from sun burn, and prevents the edible part from turning green and developing a bad flavor. Some varieties are actually self-blanching, and have the tendency to curl their leaves over the head. Keep in mind that the blanching process is only necessary with white varieties, since colored ones need the sun to become purple, orange or green.
No matter their color, cauliflower plants have a shallow root system – so you’ll want to avoid cultivating/weeding as much as possible.
FERTILIZING AND/OR MULCHING
Work 1-2 pounds of a complete fertilizer (like 10-20-12) per 100 square feet (9m2) into the first 2-3 inches (5-7.6cm) of your soil. You can also apply 2-4 inches of well-composted organic matter before planting.
About 4 weeks after transplanting or thinning, apply a half cup per 10 feet (3m) of row using a nitrogen-based fertilizer. Simply place it 6 inches next to your plant, and then water it into the soil (a process called side-dressing).
You can apply straw, wood chips or grass clippings to your plants when temperatures rise above 80°F (26°C). This will cool down the soil, reduce water stress, and control any weeds around your plants.
TRANSPLANTING BEST PRACTICES
Only transplant once your soil has warmed up to 50°F (10°C) and your seedlings have 4-5 true leaves. Typically, it takes about 5-6 weeks of growing transplants indoors before they’re ready to go into your garden.
Be sure to fertilize your developing transplants two times a week with a 20-20-20 soluble fertilizer.
Before you transplant though, you’ll first want to harden-off your cauliflower plants. Start moving them outside roughly 3-4 days before transplanting, into a sheltered spot. This will toughen them up and get them used to outside conditions – which can help limit their shock and prevent premature head growth.
GROWING STRUCTURE OPTIONS
A great option to improve your soil’s drainage, while also having a higher soil temperature than the actual ground. Raised beds help prevent the spread of certain diseases that thrive in cool and/or moist conditions, which is great for your plants. Finally, they help minimize any disturbances around your plants, since you don’t have to walk on their soil as you work on them.
Containers and pots can also be an option, but they need to be big enough to accommodate the whole plant. They should be at least 8 inches in diameter per plant at the top. They’ll also need holes in the bottom to allow for good water drainage.
With this option, your cauliflower has the most space to grow. First, you’ll want to check your soil for its fertilizer needs as well as any possible disease infection before you plant. Usually with open fields, you don’t have to water your plants as regularly as you would with container plants.
COMPANION PLANTS DO’S AND DON’TS
Chamomile and garlic improve the growth and flavor of cauliflower, so they make great companions. Dill also improves their growth and health, while mint helps deter cabbage moths and ants. Rosemary and sage can also be planted with your cauliflower.
Eggplants, peppers, tomatoes, and potatoes should all be avoided. These vegetables have different soil requirements than your cauliflower, so they won’t grow well together.
Common challenges and their solutions
There are a few pests and diseases that can potentially harm your cauliflower plants. Not to worry – we’ve outlined them below, as well as how to either avoid or fix the problem.
CABBAGEWORMS AND LOOPERS
Adult cabbage worms are white butterflies, while adult loopers are gray or brown worms. These worms and loopers hide in the cauliflower head and feed on its leaves.
Solution: Hand-pick the worms and loopers from your plants.
These are small black beetles that feed on seedlings and jump when they’re disturbed. Their feeding damage can potentially kill your young cauliflower seedlings.
Solution: Use a lightweight floating row cover at the beginning of the season to prevent them from becoming an issue.
You can also try a homemade spray using 2 cups of rubbing alcohol, 5 cups of water, and 1 tablespoon of liquid soap.
Test out this mixture on a single leaf first, let it sit overnight, then spray the rest of your plant if you don’t notice any side-effects.
Dusting your plants with plain talcum powder can also help, as well as using white sticky traps to capture these pests as they jump.
CABBAGE ROOT MAGGOT
These larvae feed on the roots of your cauliflower, and can actually destroy the whole root system. The first signs of damage from these pests are the wilting of your plants in hot weather or the yellowing or purpling of their leaves. Later on, they’ll collapse - and can die completely.
Solution: To keep populations low, rotate your crops. Also, promote plant growth so that they can deal with possible infestations.
Green or black insects that feed on the undersides of cauliflower leaves, causing them to curl and crinkle.
Solution: You can either apply insecticidal soaps or use a strong water stream to wash the aphids off your plants.
Infected roots will be unable to absorb water and nutrients. Unfortunately, this disease can already be well-established before you can see any symptoms above the soil. The lower leaves of your plant might yellow and fall off, while roots can get infected by other diseases that cause them to decay and die off.
Solution: Maintain high levels of calcium and magnesium in your soil, while also improving its drainage. You’ll also want to practice long crop rotation times (ideally 5-7 years). Make sure you practice good field sanitation, and don’t move any infested soil into healthy areas.
ALTERNARIA LEAF SPOT
This disease causes yellow and dark-brown to black leaf spots with target-like rings to appear on your plants, while the centers of these lesions might dry and fall out. They can appear on the stems and leaves of your cauliflower, and can sometimes lead to the decay of the heads. Lesions can also act as entry points for other rotting diseases to take hold.
Solution: Plant certified, disease-free seeds and practice long crop rotations. Try to minimize long periods of leaf wetness by watering your plants in the morning and also by avoiding overhead watering. Also, make sure to space out your crops properly so that they aren’t planted too densely.
Yellow, v-shaped lesions will appear that usually cause the wilting of your plant’s leaves. This disease also causes the blackening of veins. Typically, its symptoms can be similar to those of drought stress, overwatering, or too much fertilizer application.
Solution: Treating your seeds with hot water (122°F (50°C) for 15-30 minutes) can help to kill the bacteria before planting. You can also buy certified, disease-free seeds when they’re available.
Make sure to use clean flats to start your seeds, and increase spacing between your plants to avoid any moist conditions.
Monitor your transplants, and as soon as you see symptoms of black rot, be sure to remove and destroy any infected plants.
Also, practice good crop rotation and avoid overhead watering – and don’t work in your garden when it’s wet.
This disease starts as light lesions on the stem, which then turn brown with a black border and become sunken. They might also go below the soil and attack the roots of your plants. Typically, this disease causes wilting and plant death.
Solution: Practice a four-year crop rotation. Promote good air circulation by spacing your plants apart properly, and make sure you have good soil drainage. Control weed growth around your plants and avoid working in wet fields.
This is a fungal disease that affects young plants and transplants. The stems become water-soaked and will eventually collapse.
Solution: Promote good air circulation by not crowding your seedlings, and avoid overwatering your plants.
Harvesting and storing
Typically, plants are ready to harvest once your cauliflower is about 6-12 inches (15-30 cm) in diameter.
To harvest your crop, simply cut the main stem at soil level – leaving some leaves attached to protect the white head during handling and storage.
The heads become ricey when they’ve overmatured, so make sure you don’t leave them in the ground for too long.
Either use your cauliflower right away, or break it up into chunks, store in plastic bags, and freeze them.
In general, cauliflower can be stored at 32°F (0°C) for about 1-2 weeks.