Gardening with bulbs

The bulb planting season is upon us. Amongst the first bulbs to arrive are prepared hyacinths and paper-white narcissus for indoor planting. For outdoor bulbs such an early start is not necessary.

Forcing bulbs

If you contemplate forcing bulbs for an early display, planting during the next couple of weeks is vital. This is particularly pertinent for hyacinths if you wish to get them into flower by Christmas. The end of August is the very latest by which they should be planted.

Always purchase the best bulbs that you can afford and use a proper compost or bulb fibre. Specially prepared bulb fibre is generally the best, for it has an open free-draining structure which is a great advantage when shallow bowls are used.

When planting hyacinths in bowls, leave the ‘nose’ of each bulb just poking out above the surface of the bulb fibre, and always plant a single variety to each bowl, otherwise there will be no uniformity of flowering. Varieties of hyacinth, even of the same colour, can flower as far apart as three or four weeks. Even within a single variety the flower spikes may vary from plant to plant in their period of opening.

If you are growing several bowls of the same variety, then plant all the bulbs together in a deep tray. Once they are well rooted, put those with comparable rates of growth in the same bowl. They will quickly re-establish if lifted carefully with a rootball. This is how the florist achieves even flower spikes and matching heights in a single bowl.

The most important factor in growing successful forcing bulbs is the initial rooting period. Once planted, the bulbs must remain in a cool place for eight to eleven weeks. This enables the bulbs to make a root system that is capable of coping with the burgeoning growth that is associated with forcing. During their cool period check periodically to see that the bulb fibre remains moist, but never allow it to become wet. After a minimum of eight weeks the emerging flower spikes will just be poking out of the bulbs. You can then stand them in progressively warmer conditions.

As with most flowering pot plants, during the short dull days of winter hyacinths must be given maximum light, but a temperature that is sufficiently low that growth does not become distorted or elongated. A window is fine, but do not shut them behind the curtains in the evening as the temperature drop can be sudden and quite damaging.

If a suitable light to temperature ratio can be attained, then the average bowl of hyacinths is good for four or five weeks. Once flowering has finished, the bulbs are best discarded. Unlike daffodils, which will give a reasonable show the following year when planted out in the garden, hyacinths exhaust themselves when forced and rarely produce more than a few leaves and a sickly flower stalk.

Outdoor bulbs

With spring floral displays bulbs are often used as a backbone. A firm and definite skeleton to the design. As most bulbs are relatively predictable in height, colour and spread, the varieties that are selected can be planted with mathematical precision.

It is the bedding plants that are associated with them that are less formal and unpredictable. This particularly applies when forget-me-nots are used with tulips. Although tulip and forget-me-not combinations are sometimes regarded as outdated by modern gardeners, they do still have an appeal, especially to those who like to use them informally as highlights in the border to create a traditional cottage garden atmosphere.

This also comes across when grape hyacinths are used with forsythia. Few plants will grow beneath forsythia, but fortunately blue grape hyacinths are quite happy and these usually flower at the same time.

It is easier to put together a combination if one component is other than flowers. The vivid crimson stems of the red stemmed dogwood when grown as a stooled plant are in their naked glory throughout the winter. Scatter single white snowdrops amongst them to produce a January picture of rare beauty.

Apart from using them as highlights around the garden, spring flowering bulbs have an important part to play in more ephemeral situations. Not just as traditional bedding, but in containers with contrasting and complementary plants such as dwarf wallflowers and universal pansies.

With containers it is possible to achieve a number of successional displays by planting bedding and bulb combinations into inserts. These are like wire trays which fit into the planters and contain all the compost and plants. They are removed and replaced as each display fades.