While there is increasing interest in bluebells, there is also increasing controversy. The wild native bluebell has a drooping head of narrow bell-shaped, violet-blue flowers, which are arranged on one side of the stem. By contrast, its relative the Spanish bluebell has larger, broader, more open flowers, light blue in colour and arranged all around the stem, giving it an upright flower head.

It gets even more complicated, because there are hybrids between the wild bluebell and the Spanish garden bluebell. These are intermediate in character to varying degrees, from being practically native to almost completely Spanish.

The Spanish bluebell doesn’t retire into the shadows as the native species does. So it has been favoured in gardens since it arrived from Spain, perhaps 300 years ago. It is usually grown in flower beds, in big clumps of strong, broad, dark-green foliage.

As the clumps get quite large, it is not unusual to have surplus bulbs and these were often thrown out of the garden to roadsides and other waste ground. These bulbs, and the ones in the gardens, have hybridised with the wild bluebell by visiting bees carrying pollen to nearby clumps. There are pink and white forms of both species and these sometimes appear naturally in otherwise blue populations, but they have been cultivated too.

There is some concern that the truly wild bluebell is being ousted by vigorous hybrid bluebells, although it remains to be seen how well they cope with shade in comparison with the native.

It is good to have genetically pure stands of the wild bluebells because they create a look that is unique — a dark water-blue appearance set in pools of blue under open woodland.

The lighter colour of the hybrids is pretty, but it is not as entrancing as the blue of the wild flowers.

There is already widespread adulteration of the genes of the wild bluebell and this is likely to be unstoppable.

In the meantime, there is a continuing source of Spanish genes flowing into the wild population, even as the latter tries to back-cross it out.

While the removal and destruction of Spanish bluebells is not generally warranted, though it has been discussed, there is probably a case for their removal from country gardens in isolated areas where there is likely to be relatively few sources of Spanish pollen.

Bluebells, wild, Spanish and hybrids, can become nuisance weeds in gardens. They produce a lot of seeds and these generally pop up close to the parents, but may also find their way around the garden.

Seedlings can appear in the centre of other plants, even in small shrubs. These are difficult to remove, the bulbs often being quite deeply set, the foliage breaking off but re-emerging the following spring. Glyphosate works, but often needs to be repeated. While bluebells can be a weed in flower beds, they are at home in a semi-wild setting. They can make a fine show in a sizeable drift, in a grassy area under trees contained in the garden and not too close to a boundary where they might march out into surrounding hedges or other ground.

If you want to start a show of bluebells, try to find a source of seed. This is ripe in July and can be simply scattered over a suitable area as soon as picked. Seed should not be taken from wild plants, but can be collected from plants in gardens. CL

Poached egg flower

The poached egg flower, or bee flower as it is sometimes known, flowers in late May and June and is one of the best bee forage flowers there is. It produces lots of nectar when the flowers are open and are continuously worked by bees, but it is also visited by hoverflies.

Bee-like or wasp-like hover flies are tremendous predators of greenflies. The plump larvae feed voraciously on greenflies, destroying the colonies into which the female hoverflies lay their eggs.

So, growing poached egg flower, or limnanthes (originally from California) is a good way to deal with greenflies. Sow the seeds in August or in spring. Once sown, the plants self-sow and continue to come up for years after.

Trees, shrubs & roses

If necessary, continue to prune spring shrubs as they go out of flower, such as forsythia, flowering currant, kerria and spring spirea. Tie in the new shoots of climbing roses so that they will be in the correct position for training later. Spray roses against blackspot disease, especially in the damper parts of the country.

Fruit, vegetables & herbs

Control weeds and thin out vegetables that have reached suitable size. Complete sowing of maincrop vegetables, such as carrots. Repeat sowings of lettuce and peas. Sow cabbage and cauliflower for autumn and winter. In mild areas, plant out tender vegetables such as sweet corn.

Lawns

Lawns have had a good run in recent weeks, with soil temperatures ahead of normal. Growth is good and the lawn is unlikely to need feeding, but a lawn that is pale or growing poorly should now get some lawn fertilizer or high-nitrogen fertilizer. Carry out any lawn repairs or over-sowing soon, before the soil dries out.

Flowers

Bedding plants should be planted out in the coming two weeks. Nights have been mostly cool, if not frosty, so never be in a hurry with bedding plants unless you are in a very favoured locality in the south of the country. Dahlias and corms of gladioli can be planted out where they are to flower.

Greenhouse & house plants

Plant out tomatoes, chilli peppers, cucumbers and sweet pepper plants as soon as space becomes available in the greenhouse. If you have not raised plants, they are available in garden outlets. Feed greenhouse plants strongly now to get good growth before mid-summer. Water well.