OnMySill

Spring Crocus / Dutch Crocus

Crocus vernus

description

Spring Crocus is a small early-flowering corm with cup-shaped blooms in bright spring colours.

benefits

  • Flowering
  • Suitable for containers

How to care for Spring Crocus

sunlight

Spring crocus grows in open meadows and beneath deciduous trees, where it gets strong early-season light before the canopy fills in. Give it the brightest spot available while it is growing and flowering.

Full sun

Best for sturdy growth and plentiful blooms. Outdoors, plant where it receives about 6 hours of sun in spring. A sunny south-facing window suits potted bulbs, provided the pot stays cool.

Light shade - tolerated

Light shade is suitable under deciduous shrubs or trees, since crocus finishes much of its growth before leaves cast dense shade. Avoid deep, year-round shade, which reduces flowering.

Place pots close to the glass in a bright window, and turn them every few days if growth leans toward the light.

watering

Keep Spring Crocus lightly moist while it is rooting, growing, and flowering, but let the compost dry once the foliage has finished.

Autumn - spring growth

In pots, water thoroughly about every 5-10 days, or when the top 2-3 cm of compost feels dry. In the ground, rainfall is often enough; during a dry spell, soak the soil roughly every 7-10 days. Let excess water drain away.

Lift the pot after watering, then again before watering: a much lighter pot is a reliable sign that the root ball is drying.

After flowering and summer dormancy

Continue modest watering while the leaves are green, then stop when they yellow and die back. Keep dormant corms nearly dry until autumn growth begins again.

Warmth, sun, small terracotta pots, and a gritty mix dry faster than cool weather, shade, large pots, or heavier compost. Check the soil rather than following the calendar.

Never leave dormant corms in wet compost, as they can rot.

humidity

Normal home or outdoor air

40-60%

Spring crocus grows through cool, often damp spring weather, but it does not need high humidity. Average household humidity is suitable, and established pots are happiest outdoors in cool air.

In heated rooms, very dry air can make flowers fade sooner and the potting mix dry unusually fast. Keep the compost lightly moist while the plant is growing rather than trying to humidify the room.

Do not mist the blooms - move a potted crocus to a cool, bright spot if indoor air is hot and dry.

temperature

Growing and flowering

4-16°C (39-61°F)

Chilling for indoor blooms

2-9°C (36-48°F)

Spring crocus comes from cool European meadows, so it flowers best in chilly spring weather. Keep potted plants cool and bright to extend the blooms. Corms grown indoors need a cold period before they can flower.

Place flowering pots in a cool, bright spot away from radiators. Warm rooms make the flowers fade quickly.

nutrition

February - May

Feed container-grown crocuses about every 3-4 weeks while leaves are actively growing, using a balanced liquid fertilizer at half strength. In garden soil, one light application of bulb fertilizer as shoots emerge is usually enough. Stop once the foliage yellows and dies back.

Phosphorus

Phosphorus supports root growth and helps the corm store energy for next spring. A fertilizer made for bulbs supplies it without pushing overly leafy growth.

Potassium

Potassium helps the leaves build and move stored energy back into the corm after flowering. Normal bulb fertilizer provides enough.

Feed only on already moist soil, then let the leaves fade naturally so the corm can recharge.

soil

Light, gritty, free-draining soil

Spring crocus corms need air around them and quickly rot in waterlogged soil. Use ordinary garden soil loosened with grit or coarse sand, or a potting mix with extra grit for containers.

pH 6,0 - 7,5

This is slightly acidic to slightly alkaline, a range crocuses handle well. Most garden soils and general-purpose composts are suitable, especially if they are not overly peat-heavy or constantly wet.

Choose a pot with drainage holes and keep the corms out of standing water, especially over winter.