How to Grow Turnips from Seed in South Africa

Grow tender purple-and-white turnips for roasting, soups and fresh kitchen harvests, with leafy tops to enjoy too. This guide helps you sow Purple Top White Globe turnips, give the roots room to swell and choose a cool growing season for your South African garden.

Purple Top White Globe: roots and leafy tops

Purple Top White Globe is a turnip, Brassica rapa subsp. rapa, with rounded roots, purple shoulders and white lower skin and flesh. It can provide roots and cooking greens. It is different from swede or rutabaga; do not use swede harvest sizes or long-season timings for this crop. UF/IFAS explains turnip identity and dual use.

Choose Turnip Purple Top White Globe Seeds in 25 g, 100 g or 1 kg raw-seed packs from GARDENING.co.za. The growing method is the same for these pack sizes. Raw describes seed form; check the received packet for treatment and handling instructions before sowing.

Quick Grow Facts

Height and the general sowing-temperature range are supported by Botanical Interests’ Purple Top White Globe guidance, for another supplier’s seed. Garden-row spacing is adapted from Utah State University’s turnip guidance. Neither source verifies the treatment or performance of the seed in your packet.

When to sow in South Africa

Choose a window that lets the roots grow through cool weather without repeated drying or prolonged waterlogging. The regional suggestions below are practical starting points inferred from turnip’s cool-season needs and the local autumn/winter label, rather than a cultivar trial calendar. Altitude and the weather in your garden matter more than a fixed date.

Do not import Northern Hemisphere sowing months directly into a South African calendar. The RHS turnip guide supports cool conditions, small successive sowings and protection from harsh frost; its UK dates do not apply here.

How to sow and thin turnips

1. Prepare the final bed. Choose sun and a fine surface over loose, well-drained soil. Remove weeds and large stones. Work in mature compost if needed; do not put fresh manure against the seed or future food crop.
2. Sow thinly. Pre-water a dry drill, then follow the received packet. The current displayed Gardening label specifies 3 mm depth. Lightly cover and firm so the seeds contact moist soil. Do not leave raw seed uncovered on a drying surface.
3. Keep moisture steady. Use a fine rose or gentle irrigation so seed is not washed away. Check the top layer daily during dry or windy weather. Do not keep the bed flooded or sealed under an unventilated cover.
4. Thin before crowding checks growth. Once seedlings have true leaves and can be handled, snip out weaker neighbours. Retain about 10–15 cm between plants in ordinary rows. Do not pull a tangled clump apart and replant it for the root crop.
5. Match spacing to your goal. The label’s 10 × 10 cm grid suits close management and smaller roots. For garden access and airflow, use rows 30–45 cm apart. A separate row for leaf picking may use about 10 cm between plants and 25–30 cm between rows; this is a leafy vegetable row, not a sprouting or microgreen tray.
6. Repeat small sowings. During suitable cool weather, sow another short row about every two weeks rather than planting the whole packet at once.

Direct-sown seedlings do not need hardening off. Tray growing and transplanting are not recommended for this guide because disturbing the young root can compromise its shape. If protection was used outdoors, ease plants into full exposure as weather permits. For a container crop, sow into the final large pot with open drainage holes and a quality vegetable potting mix; harvest smaller roots and watch moisture closely.

Water, soil and everyday care

Aim for steady growth: repeated drought can make roots tough, and a sudden soaking after drought can encourage splitting. Water according to soil moisture and rainfall, not a rigid daily schedule. Once seedlings are established, a light mulch between plants helps conserve moisture without burying the crowns.

Use a soil test to guide feeding. Reasonably fertile, compost-enriched soil usually needs little additional fertiliser for this short crop; avoid repeated high-nitrogen feeds that favour leaves. Weed gently near the shallow roots. These watering, weeding and feeding principles follow Iowa State University’s home-garden guidance.

Protect seedlings and keep foliage airy

Inspect little holes in leaves for flea beetles, missing seedlings for slugs or cutworms, and curled leaves for aphids. Fine insect mesh over a clean new sowing can reduce insect access; keep its edges secured without overheating the bed. Remove weeds and avoid repeated brassicas in the same soil. Johnny’s cultivar guidance recommends row covers at sowing.

Persistent wet foliage and crowding favour disease. Water at soil level where practical and remove badly affected plants. Swollen, distorted roots with wilting need diagnosis rather than extra fertiliser. Choose any treatment only after identifying the problem and checking the current South African label for the edible crop and its harvest interval; this guide prescribes no pesticide or dose. University of Delaware lists common turnip pests and diseases.

Harvest roots and leaves at the right stage

For tender roots: begin checking developing shoulders before the label’s 60–80-day window. Lift a sample when it is about 5–8 cm across, or smaller for a tender young root, and judge texture. Do not wait for every root to reach the last printed day. Roots left large in hot or dry conditions can become fibrous or strong-flavoured. Loosen firm soil before lifting so the root does not snap.

For leafy tops: pick a few young outer leaves when roughly 10–15 cm long, leaving the centre and most leaves intact. Heavy stripping competes with root growth. If greens are the priority, dedicate a separate row and accept a smaller root harvest. Cook the larger tender leaves like other leafy vegetables. This harvest approach follows Iowa State’s separate root and leaf instructions.

Use clean tools, remove damaged produce and wash soil off with clean running water before preparation. Separate tops from roots and refrigerate promptly. This is a kitchen crop guide, not a promise of long storage life or seed-for-food suitability.

Troubleshooting germination and establishment

• No seedlings: inspect whether the shallow layer dried, crusted, washed away or stayed waterlogged. Check seed age and the packet directions; colder soil can delay emergence beyond the planning window. Re-sow a small section only after correcting conditions.
• Seedlings collapse at soil level: wet conditions, poor airflow or damping-off may be involved. Remove affected plants and improve drainage before resowing.
• Seedlings disappear overnight: inspect for slugs, snails and cutworms; protect the next sowing and check the bed after dusk.
• Large tops but small roots: check crowding, excessive nitrogen, weak light or root disturbance. Thin early and avoid moving retained plants.
• Tough, pithy or split roots: check delayed harvest, heat and uneven watering. Pick younger roots and try a cooler sowing window.
• Early flower stalks: temperature stress and the plant’s seasonal response can trigger bolting. A flowering root will not return to tender growth; harvest usable plants and plan a better-timed sowing.

These are likely causes, not diagnoses. For recurring losses, photograph the whole plant, root and bed and ask for local horticultural advice. The RHS guide and Utah State’s turnip advice explain moisture stress and root-quality problems.

Keep sowing seed separate from food

The harvested roots and suitable leafy tops are edible, but the seed sold for sowing is not established as food-grade. Do not eat this sowing seed or use it for sprouts or microgreens. Raw seed is not proof of untreated, organic or food-safe status. Follow all packet treatment warnings, keep seed away from children, pets and food, and wash hands after sowing. If treatment or handling information is missing, ask the supplier before use; do not try to remove a treatment by washing or soaking.

Ready to start a cool-season kitchen row? Shop Turnip Purple Top White Globe Seeds and keep your packet with your sowing notes.