Planting bulbs, corms and tubers

All bulbs and bulbous plants provide fabulous garden colour and are among the easiest plants to grow and look after.

Daffodil, tulip, crocus, lily and even dahlia, canna and gladioli all fall into the category of bulbs or ‘bulbous plants’, which includes corms and tubers. They are all swollen parts of roots or stems which, when planted, grow into a new plant.

When To Plant Bulbs

Planting bulbs, corms and tubers

There are two main planting times for bulbs:

Summer-flowering bulbs, such as dahlia, begonia, gladioli and canna lilies, are planted in mid- to late spring and early summer. Many of these plants are not frost hardy, so shouldn't be planted outside until the fear of severe frost has passed. You can always plant them up in pots in a protected area - such as a greenhouse or cold frame - and then plant out later.

Spring-flowering bulbs need to be planted in autumn, the earlier the better. The old advice was always to plant tulip bulbs in November, but there’s no proof that this has any effect and most experts now recommend planting with all your other spring-flowering bulbs.

Lilies and some anemones can be planted at either time.

How To Plant Bulbs

Before planting bulbs begins, it's always best to improve the soil first, by mixing an organic-rich compost with the soil, such as soil conditioner and enrich with plant food.

Follow the instructions on the packaging for the right depth and space apart. Bulbs always look better planted in bold clumps of one type or colour, so plant them together rather than spread far apart.

Planted bulbs look great in containers and dwarf varieties can even be grown in hanging baskets. They can also be planted in small pots, which can then be sunk in the ground or go for more ornate pots, that when in full flower is a great way of filling gaps in beds, borders and or adding colour to patios.

For more top tips on growing bulbs visit The Telegraphs: Top 20 Tips for Planting Bulbs

Growing Bulbs

Most bulbs need very little care when growing. Summer-flowering bulbs may need regular liquid feeding during summer, this is to ensure they continue to flower.

Tall varieties, particularly those with large flowers and thin stems - such as gladioli - may need staking.

Different Types Of Flower Bulbs


True Bulbs

There are two types of bulbs that come under true bulbs:

  1. Tunicate they have a tunic or papery skin covering
  2. Imbricate that does not have a skin covering



These are very similar in appearance to true bulbs, but when cut in two, you will see it is solid and does not have rings.



These are very common as potatoes start off life as a tuber, and you can recognise them as they have lots of growth nodes also known as eyes.


Tuberous Roots

These are modified, enlarged, specialised roots that store food, and are used up during the growing season, which is then replaced by new.



Very different looking from the other bulb types, as they are stems that grow sideways rather than up, which run along the surface of the soil or just below it.

For more detailed information on the different types and how they are made up click here

After Flowering

Once bulbs have finished flowering they need to be cared for so that they produce the flower buds for the following year. Start by deadheading them once the flowers fade.

It may be tempting to remove the foliage or tie it into neat knots but don’t. The bulbs need the leaves to feed them up, so they produce another wonderful display next year. Instead of removing the foliage, give the plants a feed. Liquid fertilisers are the best choice as they act quickly.

Autumn Care Of Summer-flowering Bulbs

Some summer-flowering bulbs - such as dahlias and canna lilies - are not reliably hardy and need some care and attention in autumn, depending on where you live.

In mild regions, you can leave them in the ground, preferably covered with a thick mulch of bark to provide insulation from cold and frost. You can try this in colder regions, but there is the risk that they will succumb to frost damage. Even if they survive the winter, they usually come into growth later in the year and flower later - or sometimes not at all. In such circumstances, it is far better to dig up the plants in autumn and overwinter them in a frost-free greenhouse, garage or shed.

If your bulbs are in pots outside and you're not able to bring them in, then placing bubble wrap or hessin around the pots will help keep the frost out. Also if you have space, you can place your pots together and get a fleece polytunnel to go over the top of them.

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