There is probably no more difficult plant to grow for exhibition than the Sweet Pea (Lathyrus odoratum). And there is probably no easier plant to grow in the garden for decoration, over a long period, than the sweet pea. There is no need to trench the ground 4ft deep and run the flowers up on single stems to achieve the maximum size and perfection. Sweet peas may be sown outdoors to ramble over any eyesore, like a tree trunk – and they are particularly useful for climbing up through winter and early spring flowering shrubs to give colour during the summer. The method is very simple indeed, as it relies on one of the few firm dates in the gardeners’ calendar. Seeds should be sown outdoors on 10 October – or as near to it as possible.
Seeds can also be sown in this way to grow plants on rough tripods of bean sticks to have a clump of sweet peas in a mixed border. The most showy kinds are the Spencers which can be bought as mixed seedlings, but if you wish to choose your colours the following is a selection: white – ’Swan Lake’; scarlet – ’Airwarden’; cerise – ’Percy Izzard’; carmine – ’Carlotta’; mauve – ’Leamington’; pink – ’Piccadilly’; pink and yellow – ’Frolic’. These are the classic varieties, and there is a new strain called Galaxy with larger flowers and more of them but they are only available as mixed seedlings. Buy seeds from a seedsman – and sow on 10 October.
Lathyrus grandijiora, the Everlasting Pea , is almost indestructible. I have some plants growing in a meadow which are only there because they were thrown on a bonfire. In appearance, it is exactly like a Sweet Pea, and although the flowers last only for a day so many of them keep coming that you do not notice this ephemeral quality. The leaves, too, are rather like those of a Sweet Pea and were it not for one sad fact, the two would be identical – it has no scent. Even so, it is a valuable plant to grow in a mixed border or left to wander in its own rampant way. Incidentally, one of the places where it will grow is where nothing else can hope to survive – right on the roots of a Lime tree. Buy plants from a nursery or garden centre and set them at any time in open weather from October to March.
Delightfully delicate
The flowers are distinctive, having one large upright petal and two winglike petals. The range of sweet pea colours is enormous: scarlet, crimson, maroon, purple, lavender, blue, pink, orange, cream and white. You can buy named varieties in single colours or mixtures of colours.
Sweet peas are generally bought as seeds and the big-gest selection is offered by mailorder. A more limited range is available from garden centres. You should also be able to buy young plants from garden centres in the spring, as an alternative to raising your own plants from seeds.
Image via Wikipedia
Another reason why sweet peas are so popular is that they can be grown in various parts of the garden, from containers on the patio to flower borders and even among the vegetables if you just want blooms for cutting.
All sweet peas, whether tall or dwarf, like a spot open to the sky with plenty of sun. The more sun they see, the more flowers are produced. Avoid the shade as you will not achieve the results you want. Any soil is suitable as long as it drains well and does not become waterlogged after rain.
Apart from this do not worry too much about the soil as sweet peas are adaptable. Do ensure that they receive plen-ty of water: some soils dry out faster than others, particularly those containing a high proportion of sand, gravel and chalk, so take special care with these.
Support systems for Sweet Peas
There are various ways of supporting tall sweet peas. In the flower border you could put up a 1.8m/6ft high wigwam of thick bamboo canes secured at the top with a plastic cane-support ring. The stems can be secured quickly and easily with wire plant rings.
Some of the most attractive-looking supports for sweet peas which are to be grown in prefer to grow sweet peas on netting. Choose plastic pea and bean netting with a mesh size of 13cm/5in square, or a large-mesh wire netting. It should be 1.8m/6ft high and supported with timber posts at each end. Stretch galvanised wires between the posts and tie the netting to these.
Tall sweet peas can also be grown against sunny walls and fences (a good way of brightening up an unsightly garage wall). Support them with pea and bean netting, wire netting or trellis panels fixed to the wall or fence. If you have a trellis screen or a pergola in the garden this would also make an ideal support for sweet peas. For a spectacular effect allow them to intertwine with climbing roses.
Box of delights
Dwarf sweet peas are ideal for containers such as patio tubs and window boxes. They can also make a colourful edging to a flower border. Height ranges from 30-90cm/l-3ft depending on the variety. The shortest varieties include ‘Patio’ and the tallest ‘Jet Set’.
The tallest of the dwarf sweet peas will benefit from a little support to ensure they remain upright. Use either twiggy sticks left over from blooms will last a long time in water in a cool room. The frag-rant varieties will, of course, scent the room. In fact, you may find some of them almost overpowering! Pick the blooms with long stems early in the morning and stand them up to their necks in water for a few hours before arranging. Sweet peas do not need other plant material to enchance them, although some sprays of gypsophila in an arrangement can look very pretty.
Pruning or proprietary metal plant supports – the kind that encircle clumps of plants. Both types of support should be inserted before the plants become too tall – ideally when they are about 10cm/4in high. Containers for dwarf sweet peas should be filled with a suitable potting compost. This can be a light-weight peat-based or soilless type, or one of the new peat alternatives. You might prefer to use the traditional John Innes potting compost No. 1.
Sweet peas need plenty of water to grow well — the soil must be kept permanently moist and not allowed to dry out. You will need to check containers daily, or even twice a day in hot weather.
When watering make sure you apply enough, so that it actually runs out of the bottom of the container. Then you will know that the entire depth of compost has been moistened.
