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Plant care

Turnip 'Oasis' (Oasis turnip) care

Brassica rapa var. rapa 'Oasis'

Also called Oasis turnip, sweet white turnip.

RHS H4USDA 2-9Mildly toxic to petsIndoor Roots 6-10 cm across

Watering rhythm

Direct sun (at least 4-6 hours)

Even moisture, about 2.5 cm per week

Light

Direct sun (at least 4-6 hours)

Soil

Fertile, light, free-draining loam rich in organic matter

Humidity

Ambient outdoor

Temp

10-20°C

Pet safety

Mildly toxic to pets

Mature size

Roots 6-10 cm across

Care at a glance

Light

Aim for at least 4-6 hours of direct sun on the leaves. Full sun, 6 or more hours daily, for the sweetest, fastest roots; tolerates light shade but flavour and size are best in the open. If your only bright window faces south, that's perfect for turnip 'oasis' — same window any aroid would fry on.

Watering

Crops like turnip 'oasis' reward consistent watering — even moisture, about 2.5 cm per week. The mistake is the daily light sprinkle: it never reaches the deeper roots. A long soak twice a week beats a five-minute splash every day. Consistent moisture gives the crisp, juicy texture this variety is grown for; drought stress makes roots fibrous and sharp. Keep the soil evenly damp throughout growth.

Soil and pot

Turnip 'Oasis' grows best in fertile, light, free-draining loam rich in organic matter. Loose, fertile soil produces smooth, mild roots fast. Keep pH 6.0-7.0, lime acid ground to discourage clubroot and avoid fresh manure, which can fork the roots. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Turnip 'Oasis' sits happiest at around Ambient outdoor humidity and 10-20°C (50-68°F). No specific humidity requirement; space plants for airflow to keep the foliage free of mildew in humid conditions. If you keep the room above 10 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed turnip 'oasis' sparingly. Moderate feeder. Fertile, compost-enriched soil supports its quick growth; a balanced early feed helps. Avoid excess nitrogen, which softens roots and pushes leafy tops over crisp eating quality. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on turnip 'oasis' in the Growli community. Each is annotated with the most common cause so you know where to start.

  • Flea beetleTiny holes peppering young leaves slow the early growth needed for sweet, tender roots; protect seedlings with fine mesh and keep them watered.
  • Loss of crispness in heatWarm weather and water stress turn the sweet flesh sharp and fibrous; grow in cool spring or autumn and harvest young for raw eating.
  • ClubrootBrassica soil disease distorting roots; rotate brassicas on a 3-4 year cycle, improve drainage and lime acid soil.
  • Splitting if over-matureFast-growing roots crack if left in the ground too long; pick at 6-8 cm and sow successionally rather than holding the crop.

Propagation

From seed only. Sow direct about 1.5 cm deep where they are to grow; do not transplant. Thin to 8-10 cm apart and sow in small successional batches for a steady supply of sweet salad turnips. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Turnip 'Oasis' is mildly toxic to pets. 'Oasis' is a Brassica rapa cultivar, which is not individually listed by the ASPCA as toxic or non-toxic; do not assume pet-safe and verify with a vet. As a brassica it contains glucosinolates and SMCO, associated in large or prolonged amounts with thyroid (goitre), anaemia and digestive upset in grazing animals; small occasional servings of the root are generally low-risk. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Turnip 'Oasis' care — frequently asked questions

What is the common name for Brassica rapa var. rapa 'Oasis'?

Brassica rapa var. rapa 'Oasis' is most commonly called Turnip 'Oasis', but it is also known as Oasis turnip, sweet white turnip. The names refer to the same species, so care instructions for Turnip 'Oasis' apply identically to anything sold as Oasis turnip.

How much light does turnip 'oasis' need?

Turnip 'Oasis' grows best in direct sun (at least 4-6 hours). Full sun, 6 or more hours daily, for the sweetest, fastest roots; tolerates light shade but flavour and size are best in the open.

How often should I water turnip 'oasis'?

Water turnip 'oasis' even moisture, about 2.5 cm per week. Consistent moisture gives the crisp, juicy texture this variety is grown for; drought stress makes roots fibrous and sharp. Keep the soil evenly damp throughout growth. The finger-test (or lifting the pot to feel its weight) beats a fixed weekly calendar because pot size, light, and season all change how fast the soil dries.

Is turnip 'oasis' toxic to cats and dogs?

Turnip 'Oasis' is mildly toxic to pets. 'Oasis' is a Brassica rapa cultivar, which is not individually listed by the ASPCA as toxic or non-toxic; do not assume pet-safe and verify with a vet. As a brassica it contains glucosinolates and SMCO, associated in large or prolonged amounts with thyroid (goitre), anaemia and digestive upset in grazing animals; small occasional servings of the root are generally low-risk.

What USDA hardiness zone does turnip 'oasis' grow in?

Turnip 'Oasis' is rated for USDA zone 2-9 (grown as a cool-season crop) and RHS hardiness H4. Outside that range, grow it as a container plant that overwinters indoors before the first hard frost.

Turnip 'Oasis' deep-dive guides

Every aspect of turnip 'oasis' care, each with its own calibrated guide:

Related guides

Turnip 'Oasis' is also commonly called Oasis turnip or sweet white turnip.