Hyacinth Splendid Cornelia

You can plant hyacinths from early March right through to the end of May.

In the garden, you need to plant in a well-drained area as hyacinths don’t like wet feet. Raised beds give great drainage if the area is a bit too wet. The bulbs do not need any fertiliser at planting time, everything they need is stored in the bulb itself.

In pots, choose a good quality potting mix with some slow release fertiliser in it as they are confined to a smaller space, they will benefit a little fertiliser. You can plant a bit shallower in pots as it leaves more room beneath the bulbs for the roots, but the pot should still have a reasonable depth as the bulbs like to put out long roots and should be covered by at least 5cm of mix.

In the garden, there’s little more to do after planting and watering in. In early spring as the shoots emerge, fertilise with a balanced N:P:K 15:10:10 fertiliser to give the plants a boost.

With pots, there are some very important dos and don'ts after planting. Hyacinths, like tulips, need to have a cold period after planting so they can develop the flower bud properly before spring. Planting hyacinths in a pot in autumn and then sitting the pot in a nice sunny area is the worst thing you can do, because pots warm up rapidly in direct sunshine, even in winter.

After planting, move the pot to a cool, shady position in your garden. Bring the pots out into a sunnier position and fertilise on the surface of the pot in early spring.

Regular watering to keep the mix just damp in pots is the best.

To ensure good flowering next year, make sure you keep looking after the bulbs after flowering.

Growing hyacinths in glasses is one of the most popular ways of getting bulbs to flower earlier than their natural time (bulb forcing). It lets you bring the delightful perfume of hyacinth flowers into your house in mid winter, and it’s great fun and educational for kids as they can watch the growth of the bulb from roots to flowering. All you need to start forcing bulbs is a good-sized hyacinth bulb, a hyacinth glass and water.

1. Place the bulb so it sits on the narrowed neck of the hyacinth glass, as shown. Fill the glass with water to just below the bulb and add a piece of charcoal to help prevent algae growth. Adding a quarter teaspoon of cut flower food as supplied with floral arrangements will help to feed the bulb as it grows, but it is not essential.Put the glass with the bulb into a cool dark place for two months – the fridge is ideal. Check it weekly to make sure the water level remains just under the base of the bulb so root growth is encouraged.

2. After eight to ten weeks, bring the glass out into a dimly lit place. By now the bulb has had a long enough cold period to start the flowering process. The roots should have developed down into the water and the shoot may be up to 4 cm long already. The leaves can also be up to 4 cm long at this stage. If the roots have not developed well then a few weeks longer in storage will be necessary, as roots must be present before sustained top growth begins.

3. Over a period of three weeks, slowly bring the vase into stronger light and a warmer position, but no more than 18 degrees. Too much warmth at this stage can result in a rush into flowering before the stem has developed to a good length, or very weak stems which will topple over.

4. Four to six weeks after bringing the glass out of cool, dark storage your flower will be in full bloom. Keep it in a well lit position now, but out of full sun which will cause the flower to age quickly. After flowering, the bulb can be carefully transplanted into soil in the garden. It has given up most of its energy by flowering early, and will need to recover in the garden for two seasons before it will be strong enough to force again.

For detailed information see our Fact Sheet on Growing Hyacinth in Glasses.

What’s the problem?

You probably need to consider refrigeration if your flowers have unusually short stems or your bulbs occasionally fail to flower altogether.

Why does it occur?

Hyacinth are native to areas which experience quite cold winters, and they need this cold period for the bulb to complete the development of the flower bud deep inside.

An insufficient cold period results in flowers on very short stems or sometimes no flower at all.

Are there any alternatives to chilling?

A number of things may help you get good hyacinth flowers without chilling:

• All tulips should be planted later in autumn when the soil temperatures are cooler, ideally below 12°C. Mid May is an ideal time in warmer areas.

• Plant the hyacinths 12-15 cm deep as the soil is cooler at that depth. The bulbs cope very well as long as the soil has been well cultivated below the planting depth so they can easily push their roots out.

• Avoid planting hyacinths in pots - pots warm up very quickly, even in winter, when the sun is on them. Bulbs really don’t like this fluctuation with warm days and cool nights, they much prefer the steady cool conditions in the garden soil.

• Use a mulch to help keep the soil cooler.

How do I go about chilling?

The most important point is that you need to chill, not freeze! Don’t put bulbs in the freezer as this is too cold and will kill them. The average fridge is at approximately 4°C and this is an ideal temperature.

Place the bulbs in a breathable container such as a paper bag and start chilling in early April. You should not start too early as the bulbs are not at the right stage of development for chilling until early April. Plant in late May.

Are there any problems to watch out for?

Done correctly, chilling your hyacinth will result in perfect flowers next spring. However, if it is not done well, keeping bulbs in the fridge can cause as many problems as it solves.

• Using a paper bag or open container is very important so the bulbs can breathe. Plastic bags cause sweating and will cause mould and rot to develop.

• Keep the bulbs to the side of the fridge, not at the back where the cooler plate may ice up and damage them, or where condensation may cause mould to develop.

• Ripening fruit, and to a lesser extent, vegetables, release a gas called ethylene.

This gas causes other fruit to ripen in a chain reaction. However, ethylene has a down side as well. It can cause severe damage to the developing flower buds in bulbs, often resulting in complete loss of the flower.

Don’t keep fruit in the same fridge as bulbs, and include an ethylene absorbing sachet in with the bulbs to prevent ethylene damage and suppress mould growth.

These can be purchased here: Ethylene Absorbing Sachet

For detailed information see our Fact Sheet on Bulb Chilling.