Growing cauliflower from seed is one of the most challenging gardening projects out there. The plant likes growing in cool conditions with quite high humidity. They need a deep rich soil that is kept well-watered throughout the season. You might end up with tiny heads if you weren’t able to provide them with what they need.
What is the Best Month to Plant Cauliflower?
Planting can be done in late March, early May, and early June. It’s best they’re sowed in modular trays since it would have an excellent crop establishment, will provide uniform plant development, allows quick transplanting with minimum root disturbance, and provides the plant with a head start against the weather, garden pests, and diseases. If you’re ready to start growing your cauliflower from seed, choosing the right month is very useful especially here in the UK.
Guide to Growing Cauliflower from Seed
The seed compost needed should have a finer texture and lower nutrients than the standard multipurpose compost. The module tray you’ll be using should be approximately 2in deep, and they’ll need to be filled with compost. Give your tray a sharp bang on the table to let it settle as the transporting of compost might create lumps that you cannot see. Make small 1.5cm deep depressions in each of the cells. Sow 1 or 2 seeds per module, and remove the weaker seedling when 2 emerges.
Cover your seeds with another layer of compost, and scrape across the top to remove the excess. Water your seeds gently using a plastic bottle with small holes in its cap. Place your trays in your greenhouse, polytunnel, cold frame, or windowsill to let it germinate. If you’re sowing your seeds in March, use a propagator, heat mat, or a warm south-facing windowsill to give warmth to your seeds. They’ll be ready to be planted out in about 4 weeks.
Care for Cauliflower Seedlings
To successfully grow cauliflower from seed, make sure you care for the seedling. Growing cauliflower seedlings indoors means that you’ll have to be careful with them becoming leggy. Seedlings tend to become leggy because they receive too much heat and not enough light. Make sure to give them as much light as possible.
If you’re using a heat bench or a propagator and they’re becoming leggy, you might want to turn the heat down and provide them with as much light as possible. If 2 seedlings appear in one cell, remove the weaker one by nipping them with your fingernails or with a sharp scissor to prevent damaging the roots of the stronger one.
Watering Cauliflower Seeds
Your seedlings should be properly watered before planting them outside. However, it’s still better to under water them than over water them, this makes them push harder to find water and develop a better root system.
Keep in mind that if the compost plug becomes completely dried out, it will form a crust that would hinder it from absorbing moisture the next time you decide to water it. If the weather is hot, water twice a day. If the weather is normal, you may water every 2 days.
The key tip for Growing Cauliflower from Seeds
Have you heard of hardening off your seeds? You’ll have to do this procedure to let your plants adjust to the conditions outside before planting them out. This process may take a week or 10 days, depending on the weather conditions outside.
Use a cloche or a mini greenhouse. Leave the cloche off the plants when the days are dry frost-free and put the cloche back at night. Gradually increase the time when the cloche is off until you finally keep the cloche off. You may just move the plants outside and put them back in if the weather is mild.
If you’ve grown your seedlings on a windowsill, leave them in an unheated room for a day or two before doing the process of leaving them outside.
Planting Out your Cauliflower
Cauliflowers are planted 60cm between plants and 60cm between the rows. The distance is to encourage them to grow bigger heads. You can grow mini cauliflowers by plantince them 15cm between plants and 25cm between rows.
Cauliflowers need a well compacted soil, so you better be digging and adding manure in advance for them to grow well in. However, if you didn’t have the chance to do so, simply firm around your seedling with your boot.
Watering should be done an hour before planting. Plant your seedling at holes in the soil that are the approximate size of the seedling plug. Push the soil around the roots to firm them using your hands. Don’t firm down on the soil or you’ll prevent moisture from travelling down to the plants’ roots. Don’t soak your plants after planting, but make sure to water them.
Transplanting them should be done on a dull day or in the evening, this would prevent your plants from wilting due to the hot and dry day.