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Cauliflowers are a member of the Brassica family, which includes broccoli, Brussels sprouts and cabbage. They can be grown from seeds or seedlings and should be ready to eat within 50-80 days of planting depending on the variety. Traditionally cauliflowers are white, but for something different, try colours including purple, green and orange.

High in vitamin C and K, potassium, magnesium, calcium and iron, use them in tasty favourites such as cheesy cauliflower bake or try modern dishes such as cauliflower pizza or low carb cauliflower rice.

Follow our seven easy steps to successful cauliflower harvest including tips along the way.

How to grow vegetables - cauliflowers.
Tips for spring soil care - applying compost and manure

When to plant and location.

When to plant.

These days cauliflowers can be planted in almost any area of Australia. Check for local varieties.

  1. In cool and temperate regions of Australia, cauliflowers grow from April to August.
  2. In warm sub-tropical and tropical regions of Australia, cauliflowers grow from March to July.

Location.

  • Pick a position in the garden that receives at least 6 hours of sun per day.
  • Ensure plants are placed in a position away from high winds, as they can be easily damaged.
  • Cauliflowers are frost tolerant, however in high frost area, plant in raised garden beds, away from low lying areas.

Soil.

Get the soil right to harvest a bumper crop of delicious cauliflowers.

Follow our steps for easy soil preparation.

  • Cauliflowers can be grown in all types of soil, however, they must be free draining so consider raised beds or rows.
  • Add well-rotted manure and compost to the soil and dig it in to a depth of around 30cm. For a no-dig option, consider Seasol Liquid Compost.
  • The pH of the soil should be 6.5 to 7.0. If it’s too low, add some lime to the soil at about a handful per square metre.
  • Add Seasol Plant + Soil Booster (100 grams per square metre) and a fertiliser rich in potassium such as PowerFeed Controlled Release for Tomatoes & Vegetables to enrich the soil.
  • Water in well and if possible, let the soil rest for a week or two.

Step 1 – Sowing seeds.

  • Seeds can be sown directly into the ground or in seed trays and later transferred.
  • If planting into the ground, sow seeds directly from the packet, 2 to 3 seeds together every 30cm in rows 40cm apart, to a depth of about 1cm. Cover lightly with soil.
  • If planting into trays put 1 to 2 seeds in each single cell to a depth of 1cm. Cover lightly with Seasol Seed Raising & Cutting Potting Mix.
  • Water in well with Seasol as it helps increase seed germination rates (mix 30mL of Seasol concentrate per 9 litres of water).

Note: This is not cauliflower seeds, it’s just an illustration to show seeds being planted.

Step 2 – First growth.

  • Seeds will start to emerge out of the soil within 7 to 10 days depending on temperature. Use a heating pad indoors for faster germination times.
  • When cauliflower seedlings first sprout, they only have two leaves, known as cotyledons or seedling leaves. These leaves look like two fat hearts on either side of the stem.
  • Ensure your tiny plants are well watered every day and apply Seasol weekly as this will help to stimulate strong root development and promote healthy growth.
How to grow vegetables - Broccoli
How to grow vegetables - cauliflowers.

Step 3 – Baby cauliflower seedlings.

  • About two weeks after the seed leaves have opened, the true leaves will appear.
  • Thin out the weaker seedlings so that they are not competing for nutrients and space.
  • Cauliflower seedlings are hungry little creatures so give them a good feed with PowerFeed PRO SERIES for Tomatoes and Vegetables every 1 to 2 weeks. Mix 20mL of concentrate per 9 litres of water.
  • Check moisture levels daily and ensure the soil doesn’t dry out. Cauliflower seedlings will become stressed, if not watered deeply and consistently.

Step 4 – Cauliflower seedling ready for transplant.

  • Transplant young cauliflower seedlings when they have two sets of leaves or more and are about 10 to 15cm in height. This is around six weeks after sowing.
  • Plant the seedlings out 60cm apart, in rows 60cm apart. When planting a good rule of thumb is to plant them at the depth they were in the punnet. If they look a bit leggy and stretched, plant deeper covering the bottom two leaves.
  • Water newly transplanted seedlings in with Seasol to help get them over transplant shock.
  • Once a week feed your cauliflower seedlings with a liquid fertiliser such as PowerFeed PRO Series for Tomatoes & Vegetables.

Step 5 – Cauliflower plant growth.

  • Cauliflower plants like to stay moist so check soil moisture daily and water where needed. If possible water early in the morning, around the base of the plant, not the leaves. This will ensure that the leaves are dry by nightfall to prevent diseases such as powdery mildew.
  • Make sure the beds are free from competitive weeds by removing by hand. Consider planting companion plants such as nasturtiums to keep pests like aphids away.
  • Apply a layer of mulch such as sugar cane mulch or peas straw to keep the soil warm and the moisture within the soil. This also helps to reduce the number of weeds.

Step 6 – Cauliflower head formation.

  • The head is the part of the cauliflower that we eat. It’s a tight collection of unopened flower buds.
  • Every 6 to 8 weeks apply another application of PowerFeed Controlled Release for Tomatoes & Vegetables to produce a bumper crop.
  • Liquid feed plants with a combination of Seasol and PowerFeed every week. Mix 30mL of Seasol concentrate and 50mL of PowerFeed concentrate per 9 litres of water (standard watering can).

Step 7 – Cauliflower harvest.

  • Harvest cauliflower heads before they reach maturity to ensure a staggered crop.
  • If the florets of the cauliflower have started to open, then they are over mature. Remove the whole plant.
  • To harvest, cut the stalk but leave a few leaves around the head to protect it. Remove the whole plant because unlike broccoli, cauliflowers will not grow new heads.
  • Store the cauliflower in the fridge to keep it fresh until you use it.

Things to watch out for…

  • Caterpillars Hungry caterpillars love to chomp on your plant leaves. Keep a close eye on these little critters and pick them off with your hand.
  • Bolting Inconsistent watering, feeding and high temperatures can cause heads not to form properly. Plants may bolt, forming tall yellow flowers.
  • Aphids Where aphids can be a problem, spray with the appropriate pest oil like EarthCare Enviro Pest Oil insect spray to control.
How to grow vegetables - cauliflowers.

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