The beautiful magnolias of spring are still in a tail-end of flower, the ground underneath is already spread with petals and soon it will become snow-white for a time until they wither to brown, or are chewed up by the lawnmower.

There are three related kinds of these summer magnolias. The best known is probably Magnolia wilsonii, which makes a relatively small tree or large bush. The flowers appear on fairly young plants, usually just five or six years old. The beautiful pure white waxy flowers form a broad, shallow cup, and dangle on short stalks from the slender twigs, the weight of the flower tilting it down.

There is also Magnolia sinensis, the Chinese magnolia, a bigger grower, not as suitable for small gardens but a magnificent sight as a well-grown tree to about 10 metres. It has the same flowers, though sometimes not as nodding, and usually with a darker crimson-red cone-like structure at the flower centre.

In both cases, these flowers are very fragrant, a lovely light sweet scent and a real bonus of this tree, if the flowers can be reached which is not always the case with older trees. Magnolia x wiesneri is a hybrid of this species, sometimes sold as Magnolia x watsonii, a similar very beautiful small tree with fragrant flowers.

Family: Magnolia is named after the French academic botanist of the 17th century. Fossil remains of magnolia have been unearthed by archaeologists, dating back to the Cretaceous period, about 150 million years ago.

A close look at the flower of this, or other, magnolia will reveal the ancient structure of the plant. There are petals, of course, which is typical of true flowers, but at the centre of the flower is a structure that looks like a cone, a transition from conifers, to flowering plants with a stigma, style and ovary.

Garden value

The summer magnolias are just showing leaves at the moment and swelling their flower buds. Unlike the spring-flowering magnolias which flower on bare branches, the summer varieties flower after the leaves have begun to appear.

As a result, the summer magnolias flower in May and June. Indeed a few flowers can appear much later in summer too. And in some years, they might well flower in April.

Growing magnolias

While the spring magnolia is well known for the way it holds its flowers upright on the twig, in a tulip-fashion; the summer magnolias tend to have nodding flowers.

This is strange because most nodding flowers appear in the early months of the year, such as snowdrops and hellebores, the nodding habit helping to keep rain water off the internal flower parts.

If any magnolia needed protection from the rain, it would seem to be the one that flowers earlier, but not in this case because the drooping kinds are the later to flower.

Look out for any of these on sale in the coming weeks. They are worth growing for the divine scent alone and the foliage and shape of the trees are very pleasing too. They will grow in any good, well-drained soil, acidic or limy, that has plenty of humus. Plant in a sheltered spot and top up with some leaf mould every couple of years for good results.

But it is not just humans that are interested in magnolias: snails like them as a source of food, particularly when the new leaves are fresh. Snails are good climbers and can cause damage a couple of metres above the ground.

Tackling pond algae

Around now, the water in ponds begins to warm up and the pond algae will respond by growing rapidly. Soon the stringy blanket weed will 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 to about 30cm of 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 is to get a proper life cycle 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.

This week’s reminders

Flowers and pots

Containers and baskets can be planted up now. 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.


There has been such good growth that grass will not need feeding for a while. Take care of the edging now around the margins of flower beds or borders, or where a lawn meets a driveway or wall, before the grass gets long. If there are bare patches after winter, shake out some seed.

Trees, shrubs and roses

Continue to spray susceptible varieties of roses against blackspot disease, especially in the damper parts of the country. If spring shrubs are becoming mis-shapen and gangly, remove the older shoots and allow new wood to take their place. Remove and replace old shrubs.

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. Houseplants can be re-potted now. Plant out melon and cucumber plants.

Fruit, vegetables and herbs

Sowing of vegetables can continue if the ground is dry enough, especially of maincrop vegetables such as carrots, broccoli and peas. Thin out vegetables that have reached suitable size. Sow cabbage and cauliflower for winter use. Sweetcorn and runner beans can be sown directly outdoors.

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