Planting Spring Bulbs in Containers

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It’s now or never for me in terms of planting spring-flowering bulbs. As with most things in gardening there is the text book time to do it and the way things really happen. I’m a bit late for planting daffodils (Narcissus) and a tad early for tulips, but come rain or shine (currently rain), the majority of them are going in this weekend.

The same as when painting decorating, it all begins with good preparation. Planting is the easy bit. My bulbs were ordered back in the middle of July, and arrived at the end of September. Since then I have been storing them in a dry, cool, dark place, ready for planting. Bulbs are best planted straight away if you don’t have anywhere suitable to keep them, as they can can rot or grow prematurely if too warm, light or damp.

A small army of pots awaits its orders!

The joy of spring bulbs is that they are relatively inexpensive, unless you go completely overboard like me. They are also incredibly rewarding given how easy they are to plant and grow. If planting in containers they are rarely worth keeping for a second year as the flowers will be smaller. If you have space the bulbs can be transferred to the garden where they should bulk up and flower again. One exception to this is Narcissus “Ice Wings”, a scented, multi-headed, white daffodil which seems to flourish in a pot. The bulbs pictured below were first planted 2 years ago and I’ve just replanted them in fresh compost. I couldn’t believe the size they’d grown to, but a will now expect lots of flowers.

Start with a clean pot of an appropriate size for the bulbs – at least as deep as the eventual height of the flowers. Crocuses and other small bulbs do best in shallow bowls or “pans”, but daffodils and tulips are perfectly suited to normal flowerpots of 12″ diameter or larger. Use a few crocks to cover but not block the drainage hole at the bottom. There is some debate as to whether there is any value in doing this, but old habits die hard and it’s a good way of using up broken pots.

Then add the first layer of compost. I use slightly different mixes for different bulbs, but general purpose compost is fine if you can’t find specialist bulb compost. Add some potting grit if you have it to hand to improve the drainage. Fill so that bulbs will eventually be covered by 3-4 times their own height in compost. Deeper is better than shallower for most, but don’t get too anxious about it. For permanent planting in borders it’s more important to get the depth right. If you really want to cram a lot into one pot (say tulips, daffodils and crocuses) plant in layers – the daffodils first, then a light covering of compost, then tulips, more compost, and crocuses nearest the surface. The shooting bulbs will organise themselves underground so don’t worry about planting almost on top of one another. This is a good way to get a long display out of one pot.

With most bulbs it’s evident which way up they should be planted. Generally speaking the pointed end should stand upwards and the rounded end downwards. A basal disc with old roots or new ones starting to emerge is common to daffodils, tulips, hyacinths, irises and crocuses. Corms and bulbs such as Fritillaria (below – they are as smelly as they are ugly!) are slightly trickier, but keep an eye out for signs of where roots once grew.

Push the bulbs gently into the compost and arrange evenly. With pots you can afford to cram them in more closely than you might in the ground to guarantee lots of short-term colour. Avoid allowing the bulbs to touch as this can spread any diseases and rot. Again, you can’t really go wrong, so go with your instincts. Then cover with more compost until the pot is full to 2″ below the rim. This is to allow room for watering. If you are adding bedding plants to the pot, do this now taking care not to unearth your carefully planted bulbs. I’m not fan of most spring bedding, especially the huge, gaudy pansies and Polyanthus available at garden centres, but violas, forget-me-nots and wallflowers are a pretty foil for bulbs.

If you have problems with squirrels, mice or voles digging bulbs up (which we do in London), then cover the surface of the pot with chicken wire. Remove it when shoots appear or everything will get in a tangle.

Finally, I like to cover the surface with at least 1″ of potting grit. This not only gives a neat, tidy finish, but stops compost splashing up onto leaves, deters snails (but won’t stop the determined ones!) and puts Mr Blackbird off turning the surface over when he starts to nest in spring. For summer pots it also acts as a water retaining mulch.

Remember that bulbs planted in pots are more vulnerable to frost than those planted in the ground. Stand pots in a sheltered position, such as under an evergreen hedge, but don’t let them dry out. Some books recommend wrapping pots with hessian or bubble wrap, but frankly my dear, I don’t have the time!

When to Plant

Daffodils can be planted from late August and those I am repotting from last year already have good roots. They like to settle in whilst the soil is warm, and generally flower earlier than tulips. This year I am growing Narcissus “Jack Snipe”, a white flower with a pale yellow trumpet, and Narcissus “Jet Fire”, with yellow, swept back petals and an orange trumpet. Both are small, stout varieties that need no support – perfect for coastal gardens. They’re combined with F1 hybrid violas in orange, violet and purple-black which will scramble through the daffodil foliage in the spring and keep the display going a bit longer.

Tulips are best planted in November when the soil is getting cold, reducing the possibility of a fungal disease called tulip blight or tulip fire (Botrytis tulipae). The symptoms can vary from bulb rot to grey-green lesions on the leaves and may result in spotted flower petals. Since night temperatures are now down to 5 or 6 degrees centigrade I figure it’s safe enough to get going. Tulips can still be planted as late as Christmas provided the soil is frost-free. This year I am planting four varieties, orange “Ballerina” and “Orange Emperor” and white “Purissima” and “White Triumphator”. These have been chosen to give a range of height and flowering time.

So, as the sun sets on my weekend I retire from the garden with a very stiff back and only a few bags of tulips left to plant. These can wait until we get back from holiday. In the meantime the majority can get settled in for the winter and the pots will be moved into situ once they come into flower. If you’re planting bulbs in containers over the next few weeks let me know how you get on and if you have any useful tips.