Common name: foxglove, named after the finger-like tubular flowers.

Botanical name: Digitalis purpurea, “digit” referring to the fingers. It is the origin of the heart stimulant drug, digitalis. The native foxglove is to be found all over the country, growing on roadsides and hedges and at the margins of woodland.

Garden use

It is best grown as a semi-wild plant, in an area of the garden where it can look natural along with shrubs and trees as backdrop, and with whatever other low vegetation exists, such as primroses, bluebells and light grasses.

It will tolerate partial shade and looks very well flowering in such places as the tall flowers tend to reach even higher when seeking the light. The flower stems can reach to over 2m on a really big plant in rich ground, but are usually around the 1m mark or a little more.

The normal colour is purple but there are lovely white forms that can create an almost ghostly look amid trees and shrubs. These sometimes appear naturally and they have been grown in gardens for centuries. A mixed packet of seeds will give white forms and often some intermediates. Some people prefer to have only the white form in the garden and these are easy to tell apart from the purple ones as seedlings – the white seedlings have no purple tinge to the leaf ribs, even as tiny plants.

Although the wild form of foxglove can be grown in gardens, plant breeders have been active and a range of hybrids are available. The best known of these are the Excelsior hybrids which feature pink, purple, pale yellow and white forms. The hybrids have heavily spotted flowers. The wild foxglove has its flowers along one side of the stem. Many of the hybrids have flowers around the stem, although sometimes more to one side than the other. This arose because many of the species used to crossbreed, with the wild foxglove, have flower around the stem. Some of these have yellow flowers, such as the yellow foxglove, Digitalis orientalis, from Central Europe, which, although it has pale yellow flowers, has a short flower stem and is not anything like as graceful as the common foxglove.

Garden value

The colour range of the hybrids is also more garden-like. They can look very well, planted in good drifts, among other perennial flowers, or in a mixed border with perennials and small shrubs. After flowering, the stems should be taken off right away to stop any seeding that might occur. The seed stems can be left on the plants in a semi-wild setting, if the idea is to allow them to naturalise to some degree. If it is intended to have white kinds only, the stems can be taken off the purple ones. Removing the stems early often results in some late flowers, usually small but still welcome.

Foxgloves are very easy to grow, thriving in any soil that is not wet. In a natural setting they are always seen growing on dry soil in well-drained conditions.

They will grow in poor soil but stay small with short stems and fewer flowers. But they should not be given too-rich a soil.

Clean up

Algae in ponds

Pond scum.

The stringy blanket weed will soon be dense enough to trap bubbles of gas and it will float to the surface and look very scummy. This can be removed from a small pond with a split cane. Take a long cane and split it about 30cm on the top, in four quarters. This can be jabbed into a mass of blanket weed and twirled until a large blob of algae has been rolled up. Gently draw this to the edge of the pond without lifting it because the weight of the wet algae will often cause it to drop off.

While this is only a stop-gap measure, it works very well and takes only a few minutes to carry out every so often. With a bigger pond, where the algal scum is out of reach and there is just too much of it, the only solution to algal problems is to get a proper lifecycle going in the pond. This means a layer of mud and some gravel in the bottom – at least 5cm deep and as much as the depth will allow. The gravel can take over at the pond edges to disguise the mud. Once this is in place, the web of life that eats the algae and helps to deny it nutrients will slowly take over. Depending on the size of the pond, a few forks of straw speeds up this process.

This week’s reminders

Flowers

With increasing temperatures, slugs and snails can very quickly cause severe damage to susceptible plants like hostas and ligularias. Dahlias are attacked as they come through the soil and sometimes this is difficult to spot. Bedding plants should be grown on strongly.

Lawn

Once the temperature rose, there was a great burst of growth of grass and many lawns are looking well. If a lawn is growing well, it will not need feeding for a while, but as soon as its growth slows or the colour begins to fade, it should get some lawn fertiliser or high-nitrogen.

Trees, shrubs and roses

Prune spring shrubs as they go out of flower, such as forsythia, flowering currant, kerria and spring spirea, but only if necessary. That is, prune only if the plants are getting too big for the position in which they are growing, or if they are becoming misshapen and gangly.

Greenhouse and house plants

All house plants and greenhouse plants should be grown on strongly now to get good growth before mid-summer. Grape mildew has already appeared from last year’s buds and it is necessary to spray a grapevine with a rose spray if it had the disease last year. Re-pot houseplants.

Fruit, vegetables and herbs

Spray apple and pear trees for apple or pear scab disease and check for greenflies. Sowing of vegetables can continue if the ground is dry enough, especially main crop vegetables such as carrots, broccoli and peas. Repeat sowings of those sown early. Plant out herb plants.

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