Tulips are members of the lily family, and flower from March-May.
They can range in height from 100-600mm (4"-24") depending on variety.
Tulips require a cold winter season to grow successfully making them unsuitable for growing in tropical climates.
The species generally come from hot and dry areas, so it may be necessary to lift and clean bulbs annually, particularly in areas with heavy soils and high rainfall.
Manipulation of the tulip's growing temperature can allow growers to force tulips to flower earlier than they normally would.
Tulips are classified as per the following divisions:
- They are best planted circa Week 40-45 to prevent tulip fire disease.
Earlier plantings may expose them to late frosts when they emerge.
- They prefer a warm sunny position in fertile well-drained alkaline soil, enriched with garden compost.
If the soil is acidic, apply 75-100gms (3-4 oz) of ground limestone per sq. metre just before planting.
- Improve heavy soil by adding garden compost and grit or gravel below the bulb at planting time.
- Plant bulbs 150mm deep or three times their depth which ever the greater, and up to 300mm deep in lighter soils.
Do not plant deeper than 150mm on heavy soils.
Prior to planting dust dried bulbs with sulphur to minimise the chances of fungal attack such as tulip fire.
- For effect plant the bulbs in groups with 75-100mm (3"-4") between each bulb.
- If growing them in containers, plant out into pots / planters containing gritty compost.
Pot cultivation allows manipulation of growing conditions and consequently flowering times.
During winter keep the compost in containers moist to dry and water well once the shoots appear.
Fetch bowls/containers indoors to induce early flowering.
Deadhead, as the first petals fall, leaving the stems and leaves to feed the bulbs, ideally lift the bulbs when the leaves are turning yellow.
Tulip plants leave a disease as they die off in late spring so it is important to remove the flower petals as they fall.
Circa Week 20:
Cut off the plants at ground level when they have turned yellow.
Alternatively, bulbs can be lifted when the foliage turns yellow and stored in trays of dry sand in a dry place at circa 18°C (65°F) until planting time.
Prior to storing remove the offsets / bulbils.
Propagate tulips by removing offsets / bulbils from mature bulbs, which can then be placed in a nursery bed until they reach flowering size.
Species tulips readily produce seed which, if sown fresh, will develop into flowering-size bulbs in five to seven years.
When plants are in bud, keep a look out slugs and aphids as these can damage the buds.
Check over bulbs, discard any that may have rotted.
- If bulbs are purchased by mail order, unpack them as soon as they are received, and plant them in bowls of bulb fibre.
Add a sprinkling of lime into the bulb fibre prior to filling the bowl/s.
- Plant the bulbs so they are not quite touching each other and the necks are just showing above the surface of the fibre.
- Thoroughly water the bowls and place them in a cool sheltered position outside.
- Cover the bowls completely with a 100mm (4") layer of leaf-mould, sand or compost.
- If no garden space is available, store them in a cool, well-ventilated cupboard or cellar at a temperature of 9°-10°C (45°-50°F) maximum.
Periodically check the plants to ensure the fibre is moist, and water as necessary.
- When a good root system has developed and the bud can be seen or felt in the growing shoot, they should be moved into a warmer room, a temperature of about 18°C (65°F) is ideal.
- Keep the bowl/s shaded until they reach a height of 75-100mm (3"-4") when they can be exposed to full light.
The bulbs will need liberal watering during this latter period.