How to Grow Tulips in Australia

Tulips (Tulipa hybrids), in the lily family Liliaceae, are spring-flowering bulbs grown for their cup and goblet-shaped flowers in massed beds, pots and the vase. Their wild ancestors come from the mountains of central Asia, so they flower best after a cold winter. Cold-winter Canberra fills Floriade with them each spring, and the most common failure in warmer gardens is planting bulbs that never had their winter chill.

Three mistakes that matter

1. Skipping the chill in a warm garden. Tulips need about two months below 13°C to lengthen the stem and open the flower already inside the bulb. Mild winters give short stems or no flowers. Chill bulbs in the fridge first, as under Planting Bulbs.
2. Planting too shallow. Bulbs planted too shallow often stay small and fail to flower, and shallow soil heats up in Australian sun. Plant about three times as deep as the bulb is tall, so the bulb sits in cooler soil.
3. Keeping the soil wet, especially in summer. Bulbs rot in poorly drained soil, and tulips need a dry summer rest. Plant in free-draining soil or a raised bed, and stop watering once the leaves turn yellow.

When to plant

Plant once the soil has cooled after summer, from mid autumn into early winter. The old rule of thumb is to plant around Mother's Day in May. Cool districts plant a little earlier, and warm ones a little later, once chilled bulbs leave the fridge. One planting gives one flush of flowers a year.

Bulbs that arrive while the soil is still warm can wait in the fridge until it cools. Bulbs planted late in winter often flower on shorter stems.

Site, soil and setup

Australia's biggest tulip farm grows its bulbs in deep, fertile, friable volcanic soil in north-west Tasmania.

Where tulip fire has struck, plant no tulips in that spot for at least three years (see Pests and diseases).

Weed status, state by state

Cape tulip is a different plant altogether, a species of Moraea. It is a declared weed in Victoria, South Australia and Tasmania, and NSW WeedWise lists it too.

Container growing

Pots suit tulips, especially in warm zones, because the mix drains freely and a pot can be moved out of the rain or into shade. Use a pot with drainage holes, at least 30 cm wide and 30 cm deep (about 20 L). A 45 cm pot holds about 12 bulbs. Fill it with premium potting mix. Set the bulbs 10 to 15 cm deep, as in a bed, close together without touching each other or the sides. The double early 'Margarita', at 30 to 40 cm, and the Potting Mixed packs suit pots best. Treat potted bulbs as annuals for the most reliable flowers.

• Watering. Water when the top 2 cm of mix feels dry, and never leave the pot standing in a saucer of water.
• Feeding. Water in fish and seaweed blend at 25 mL per 9 L every fortnight from the first shoots. From the first flowers, switch to liquid potash at the label rate every fortnight.
• Position. Full sun while in growth. Move the pot under cover during long wet spells and once the leaves have died down.

Planting Bulbs

Tulips start from dormant bulbs, planted pointed end up with the flat, rooting base down.

Chilling

Put the bulbs in a paper bag in the fridge crisper for 6 to 10 weeks before planting. Keep them away from apples and other ripening fruit, whose ethylene gas spoils the flowers, and never freeze them. Chill in every zone except Cool and alpine, where winter does the job. Bulbs sold pre-chilled usually flower in their first year, but a spell in the fridge is a cheap precaution.

Wear gloves when handling bulbs. Sap from damaged bulbs causes an itchy rash on the fingertips known as tulip fingers.

What the store sells

Plant early, mid and late groups in one bed to stretch the display over two months or more.

Planting a bed of bulbs

1. Prepare the bed as under Site, soil and setup.
2. Take chilled bulbs straight from the fridge to the garden.
3. Set each bulb pointed end up, 10 to 15 cm deep, about three times its own height. Use the deeper end in warm zones, where the soil stays warmer.
4. Space bulbs 10 to 15 cm apart, at least twice their width, or wider in a massed bed (see Site, soil and setup).
5. Water in well, then water again only if the soil dries out.
6. Mark the spot, so a spade does not find the bulbs before the shoots appear.

After flowering: keep, lift or replace

Once the flowers fade, the leaves feed the bulb for next year, so leave them until they turn yellow, about six weeks after flowering. Where the table below says to lift, dig the bulbs then. Brush off the soil, discard any that are soft or mouldy, and dry them on a tray. Store them in a paper bag somewhere dry, shaded and airy until autumn, then chill them again before planting.

Care by growth stage

Steady moisture while the leaves are green and a dry rest once they yellow decide how well tulips flower. Feed lightly from planting, then switch to potassium as the flowers open.

Keep watering through flowering, because a dry spell then shortens the display. If growth stalls in poor soil, a light dose of all-purpose controlled release granular (NPK around 14-5-10) scratched in as the leaves appear can help. Where a dog digs, use it in place of bone meal (see Common problems).

Companion planting

Low spring flowers fill the bare soil around tulips and hide the leaves as they die down.

Grows well with

• Forget-me-nots, which flower at the same time and carpet the ground between the stems.
• Pansies and violas, low edging that hides the bulbs' bare base.
• Wallflowers, a traditional spring bedding partner that flowers alongside.
• Daffodils, which flower earlier and like the same autumn planting.
• Hellebores and other early perennials, whose leaves mask the dying tulip foliage.

Keep apart

• Vegie beds, where a bulb could end up eaten by mistake.
• Lilium in the same bed, since tulip fire can occasionally carry onto lilies.
• Beds watered all summer, where dormant bulbs rot and seldom reflower.

Harvesting Blooms

Cut tulips when the bud shows colour but before it has fully opened.

• Cut in the cool of early morning.
• Use clean secateurs and stand the stems straight in water.
• Take the stem but leave the leaves on the plant to feed the bulb.
• Grow a row just for cutting, so picking does not thin the display.

Cut tulips last about 7 to 10 days in a vase. Keep the vase where cats and dogs cannot drink the water or chew the flowers.

Common problems

Leaves but no flowers in the second year. Bulbs planted shallow, or with their leaves cut off too early, often shrink and fail to flower. Replant the largest bulbs deeper and buy fresh ones for the best spots.

Flowers fade within days. Heat and dry soil shorten the flowering period; give afternoon shade in warm districts and keep the soil moist while in flower.

Bulbs dug up. The smell of organic fertilisers such as bone meal draws dogs to dig, and they may eat the bulbs. Fence the bed or switch to a granular feed.

Soft or mouldy bulbs in storage. Damp storage or damaged bulbs lead to rot; store dry and airy, and discard any bulb that is soft or shows blue or white mould. For rot in the ground, see Three mistakes.

Pests and diseases

Most tulip trouble comes in wet springs, or where tulips grow in the same soil year after year.

Tulip bulb aphid (Dysaphis tulipae). Recorded in New South Wales, Victoria, Tasmania and Western Australia, it counts cultivated tulips among its Australian hosts. It feeds on stored bulbs as well as leaves. Check bulbs before chilling and rub off any colonies. On shoots, hose colonies off or spray an insecticidal soap labelled for aphids, at its label rate. Read more

Green peach aphid (Myzus persicae). Widespread in Australia, it spreads tulip breaking virus, which streaks and feathers the petals and mottles the leaves. Pull out and bin any plain variety that develops streaks, so aphids cannot carry the virus on. Read more

Tulip fire (Botrytis tulipae). A fungus that twists young shoots and leaves brown, scorched-looking spots on leaves and flowers, with grey mould in damp weather. Remove and bin affected plants and their bulbs promptly, and keep them out of the compost.

Garden snail (Cornu aspersum). Widespread in Australian gardens, snails and slugs chew new shoots and flowers in early spring. Hand-pick on damp evenings, or scatter an iron-based bait thinly by its label, never in heaps, where dogs cannot reach the pellets or packet. Read more

Prevention first

• Buy and plant only firm, plump bulbs, and discard any with small black specks on the outer scales, which can carry tulip fire.
• Space bulbs so air moves between the plants.
• Check new shoots on damp evenings in late winter for snails and aphids.
• Clear fallen petals and yellowed leaves from the bed.

Tips

1. Write the day the bulbs go into the fridge on the bag, so they come out on time.
2. Plant special bulbs in an old colander or open basket sunk into the bed, so they are easier to find and lift.
3. If you cannot tell which end is up, plant the bulb on its side and the shoot finds its own way.
4. Save the biggest bulbs for prominent spots, and put replanted bulbs in less important beds.

Due to quarantine restrictions and our shipping policy, we cannot send tulip bulbs to Western Australia or Tasmania.