Spinach is one of those great vegetables where you can get a fast-growing repeat harvest. Cut the older, outer leaves and let the newer inner leaves continue to grow for later harvest.

Served hot or cold, it’s one of the healthiest vegetables packed full of iron, vitamins A and C, thiamine, potassium and folic acid.

Spinach belongs to the Chenopodiaceae family including beets, chard and quinoa.

It can be grown from seeds or seedlings and will be ready to harvest within 5 to 12 weeks. Get a continuing supply of leaves by planting another batch 4 to 6 weeks later.

Follow our six easy steps to successful spinach harvest including tips along the way.

How to grow vegetables - spinach

When to plant and location.

When to plant.

Spinach grows best in the cooler areas of Australia, as if it’s too warm it will bolt and go to seed quickly. For warmer areas try planting alternatives like silverbeet and NZ spinach.

  1. In cooler areas plant seeds in late summer to early autumn 4-6 weeks before the first frost appears.
  2. In warm and subtropical climates sow seeds in autumn and grow through the coolest months of the year.
  3. For healthier spinach plants, grow alongside crops such as strawberries, broad beans and cauliflower.

Location.

  • Spinach prefers at least six hours of sun a day, so pick a position in the garden to suit this.
  • If in a slightly warmer area, pick a position that will give some light shade and protection from hot afternoon sun.

Soil

Spinach can be grown in all types of free draining soil. Good drainage is essential so that the taproot and roots don’t rot.

Follow our steps for successful soil preparation.

  1. Turn the soil over before planting so the taproot and roots have a clear path for strong growth.
  2. Add well-rotted manure and compost such as Seasol Super Compost to the soil and dig it in. For a no-dig option, try Seasol Liquid Compost.
  3. The pH of the soil should be at least 6.0, but ideally it should be between 6.5 and 7.5.
  4. To boost the soil add Seasol Plant + Soil Booster and a fertiliser rich in nitrogen such as PowerFeed Controlled Release for Tomatoes & Vegetables.
  5. Water in well and if possible, let the soil rest for a week or so.
How to grow vegetables - spinach

Step 1 – Sowing seeds.

  • Seeds can be sown directly into the ground. Place 1-2 seeds to a depth of 2-3cm, spacing them 20-30cm apart. Lightly cover with soil.
  • You can also sow seeds in cells within seedling punnets filled with Seasol Seed Raising & Cutting Potting Mix. Push 1-2 seeds into each cell and lightly cover with mix. Ready to plant seedlings are also available for purchase.
  • Spinach is also great in pots. Use a container that is at least 20cm in depth.
  • Water in well with Seasol to help increase seed germination rates.

Step 2 – First growth.

  • Seeds will start to emerge out of the soil within 7-14 days depending on the temperature. It may take longer if the temperature is cooler.
  • Each seed produces 2-3 seedlings and these are best left to grow together without thinning. This is important because spinach dislikes root disturbance.
  • When spinach seeds germinate, they have two long, thin seed leaves that look quite different from the true leaves that will soon follow.
  • Spinach seedlings can be easily damaged, especially the taproot,  so take care not to disturb the plants as they grow.
  • Water your tiny plants regularly every day and apply Seasol weekly to help stimulate strong root development and healthy growth.

Note: This seed above is of a bean not spinach, it is used to show seed germination and growth.

Step 3 – Baby spinach seedlings

  • Spinach leaves use a lot of water to keep them juicy and dark green, so water frequently to keep them looking good.
  • Apply a liquid fertiliser such as PowerFeed PRO SERIES for Tomatoes & Vegetables every week to the soil around the plants. Apply 20mL of concentrate per 9 litres of water (standard watering can).

NOTE: If the plants are slow to grow the leaves can taste very bitter.

Step 4 – Spinach seedlings ready for transplant.

  • Transplant seedlings from the seedlings you have purchased.
  • Plant seedlings at the depth they were in the punnet. Be very careful not to damage the taproot and roots, so as little handling as possible is the best course of action. Avoid planting seedlings too deeply as this can cause them to rot.
  • Gently firm around the transplanted seedlings to make sure they are secure in the soil.
  • Water your newly transplanted seedlings in with Seasol to get them over transplant shock.
  • Once a week feed your spinach seedlings with a liquid fertiliser such as PowerFeed PRO SERIES for Tomatoes & Vegetables. As the seedlings start to grow increase the rate to 50mL of concentrate per 9 litres of water.

Step 5 – Spinach plant growth

  • Watch your spinach grow over the following weeks as the stalks and leaves develop and mature.
  • Spinach leaves need plenty of soil moisture to stay juicy.
  • If possible, water plants in the morning. Direct the water onto the soil around plants and not on the leaves. This will ensure that the plant foliage can dry out before nightfall, making the spinach less prone to diseases such as downy mildew.
  • Apply a layer of mulch such as sugar cane mulch or pea straw to keep the soil warm and free of weeds.

Step 6 – Spinach harvest.

  • Spinach provides a repeat harvest of leaves over several months.
  • Start harvesting the outside leaves when there are at least 6-8 mature leaves on the plant, leaving at least 4 leaves in the centre.
  • Leaves left on too long, will become bitter and tough.
  • Once the leaves have been harvested, wash thoroughly, dry and store in a plastic bag in the crisper section of the fridge.
  • If there is an abundance of leaves, these can be cooked and frozen for later use in stews and soups.

Things to watch for…

  • Downy Mildew For an organic treatment for downy mildew, remove the worst affected leaves and spray with a homemade remedy such as a 1 in 10 mixture of full cream milk to water.
  • Aphids These tiny pests multiply rapidly and can spread virus diseases., Remove affected leaves and spray with EarthCare Natural Pyrethrum insect spray.
  • Caterpillars A variety of caterpillars love to chomp on spinach leaves. Keep a close eye on these little critters and pick them off with your hand.
  • Bolting If it’s too warm or the leaves are left on the plant too long, the plant may bolt and go to seed. Check plants daily
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How to grow vegetables - spinach

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