May is the month to think about summer bedding plants, ones that will flower on and on until the first frosts arrive. They’ll lift the garden, adding highlights of vivid colour, and are particularly useful in the dog days of August when gardens often look tired and jaded. Many will persist late into the year, because these plants tend to be sterile, so they cannot set seeds.
As a result they belt out the flowers for months on end and, now that autumn tends to go on and on, you might get colour right up until November.
Sterile plants have to be raised from cuttings which tends to make them expensive. However they outshine their seed-setting competitors by a floral mile and just one container of well-chosen plants will lift the garden. It’s worth investing in the best, not the cheapest, and many seed companies sell plug plants and garden-ready plants and you’ll find them in garden centres too.
Give your garden a makeover and save money at the same time with a special Thompson and Morgan offer of 10% off.
Compost, food and containers
Containers of bedding plants tend to cover the surface of the compost by midsummer and this leafy layer makes it difficult for rain to penetrate the roots, even in wet summers, so you will have to water regularly. However if you use a good loamy compost, such as John Innes, it will hold moisture and nutrients far more effectively than a lighter peaty or wood-based compost. If you’re away for a weekend, your plants will cope far better. Good compost, although more pricey, saves you time.
Compost and feeding
Opt for John Innes, a recipe containing loam. There are three numbers, 1, 2 and 3 and the higher the number the more plant food added to the same recipe. Be aware that the nutrients in the compost will only last for four to six weeks, so correct feeding is important. You want to promote flower, not leaf, and the easiest way to do this is to water on a liquid tomato food every week until late September. Avoid high-nitrogen plant foods because your plants will produce leaf at the expense of flower.
Find out how to improve your soil
Choosing summer containers
You can be creative when it comes to summer containers because the nights are warm enough to allow wicker baskets, metal mesh baskets, plastic or galvanised metal. Try to think of your colour scheme. Silvery plants and cool colours, such as purple or blue, look good in galvanised containers. White or pale bedding plants could look anaemic in pale pots, but highly stylish in black or aubergine containers. You could also go quirky and plant up old boots or wellingtons. If you’ve a windy garden, avoid tall tapering pots because they’ll blow over. Pots with a lip that curls over the edge should also be ruled out for this provides a refuge for slugs.
Bedding plants for partial shade
A lot of gardens are partially shaded, but some plants really enjoy this position. Begonias will thrive in partial shade and it’s the smaller flowered, seed-raised varieties that are easiest to grow. The Boliviensis hybrids have a cascade of long-petalled flowers from tip to toe and these sit just above the attractively toothed foliage. The Starshine series and the Sweet Spice Series are sold by Mr Fothergill’s, Thompson & Morgan and Marshall, among others. Wyevale also sell good varieties of begonia in store and on the web. You could go for showy doubles if you wish.
Fuchsias, half-hardy annuals that could be kept from year to year, are equally accommodating in brightish shade and they really shine once the days begin to shorten. Fuchsia ‘Blacky’ (from T&M) is a fully-skirted stunner with pink outers surrounding a sooty skirt. They also sell an orchid-pink double named ‘Pink Elephant’, or you could go for elegant simplicity. Opt for fully grown fuchsia plants, rather than plugs, unless you have a super-duper greenhouse. New Guinea Impatiens are another colourful option for semi-shade. They’re brasher and larger than busy Lizzies, which have been seen off by downy mildew, and they have dark foliage and larger flowers. Whites can look very classy in semi-shade.
Coleus 'Red Head' has vibrant foliage that grows well in shade.
There are subtler options for shade too and the plant gardeners know as coleus, but now renamed solenostemon, produces felty foliage in shades of red, lime-green and cream. Buy the most handsome plants you can find, because slugs do enjoy nibbling young coleus plants. Or use a permanent planting of hardy ferns and ivies.
Bedding plants for sunnier positions
Go for drought-tolerant plants such as scented-leaved pelargoniums (geraniums). The rose-scented ‘Attar of Roses’, or the pungent ‘Lady Plymouth’, can be woven together in one pot or they can be potted singly. Fibrex Nurseries have a vast selection of pelargoniums. The foliage varies from fine to full and using three varieties in a large container will provide a tapestry of leaf. Most of the small flowers are bee-friendly, but if you want one with a larger flower opt for ‘Clorinda’. This rugged variety, with sizeable, bright-pink flowers, has cedar-scented plain green leaves. If you want to add colour add a heliotrope. If you want showier pelargoniums opt for zonal pelargoniums or ivy-leaved forms. Fibrex send out their Fibrex Favourites every two weeks, or get in touch with the nursery.
Osteospermum 3D Berry has a large middle that stops the flowers closing in the evening.
Osteospermums are sun-loving South African daisies and new plant breeding has produced a 3D Berry series with a fuller middle. This prevents the flowers from shutting in the afternoon, an annoying trait of most osteospermums. Thompson & Morgan are doing an Osteospermum 3D Collection featuring purple, lemon ice, violet ice and yellow. If you’ve missed them this year, try to get some next year. There’s also a new single series called Serenity and these have large open flowers and dark eyes. The dark-purple form is stunning, with well-defined petals set round a purple-middle that develops a yellow haze.
Dahlias also do well in a warm, sunny position and there are several compact patio series. Most have dark foliage and lots of smaller flowers. One of the best is the soft-orange ‘Star Wars’. The deep-red ‘Pulp Fiction’ is another patio dahlia that does very well. These reach about 18 inches in height. The Happy Series, another one that is widely available and suitable for containers, is taller and reaches over 2 feet. You should find lots of potted up compact dahlias in the garden centres this month. Slugs do like the dark leaved ones so do frisk your plants at dusk.
Petunia 'Ovation Dark Heart', 2017's winning petunia at Ball Colegrave.
The other two rather similar plants that do well in the sunny situations are petunias and calibrachoa. These have saucer-shaped flowers and often come in shades of pink and purple. Recent breeding has improved enormously and now there are scented, double petunias known as Thumbelinas. ‘Priscilla’ was the first and more have followed. Every year the Banbury-based arm of Ball Colegrave get visitors to vote for their favourite flower on the trial field, using a blue flag system. The 2017 winner was Petunia ‘Ovation Dark Heart’, an eye-catching, purple-pink petunia with dark etching inside each flower. It was closely followed by the almost-black ‘Night Sky’ and ‘Black Velvet’. Dark flowers require careful placing and a bright pot to avoid getting lost in the garden.
The best way to pick plants at this time of year is to go to a good garden centre and see what they have, because online suppliers may have sold out by now. Pick out some good ones that go together and ignore anything that looks shabby. Good combinations might include a mix of pinks and purples, or it might be a collection of sunny yellows, oranges and reds, blues and yellows or pastel creams and whites. Arrange them in the trolley before you buy and, if you’re on a budget, just go for one great container. Even one makes a huge difference to any garden.
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