I have worked with many flowers in the past, but the ones which always stood out for me were the glorious sweet peas. Fragrant flowers attached to the stems of twisty tendrils is a must for all kinds of gardeners, from the amateur to the specialist. They bring back many a fond memory of childhood, when I used to grow them every year in my borders.

The botanical name for sweet peas is Lathyrus odoratus, which is an annual plant (it completes its life cycle within a year) and there are many species and varieties. They can be trained up garden canes or any suitable support, which can be used as a main feature of your garden.

Sweet peas are native to Sicily and southern Italy. The history can be traced back to the 17th Century, when the seeds were sent to England by a Sicilian monk. Dr Robert Uvedale, an expert in unusual plants, grew and observed them in his garden in Middlesex. Current species are believed to be based on a herbarium specimen grown by Dr. Leonard Plukenet in Dr. Uvedale's garden, which was recorded in 1700. Although the history cannot be confirmed, historians believe this was the case based on evidence that was uncovered.

One definite fact however, was the original sweet pea being named Cupani. This came from the Sicilian monk called Francisco Cupani, who recorded finding the sweet peas in Sicily. Cupani is still available today!

One hundred years after the first discovery, there were only about six colours available. Towards the end of the 19th Century, a man called Henry Eckford from England used hybridisation to create larger, more beautifully coloured blooms. He called these the Grandifloras, which were the new revolution in sweet peas. Some of the Eckford varieties are still available to buy today, but they are becoming rare.

Also, in the 19th Century, a head gardener to the Earl of Spencer discovered a new type of sweet pea growing naturally in his grounds. This was named Spencer's and is very popular to this day. There are now many different colours of Spencer type sweet peas which are popular because of the number of flowers there are per stem. This is the reason they are known as multiflora type sweet peas by many specialist growers.

There are now many different types and varieties of sweet pea. American breeders have contributed to the vast array of sweet peas available to buy today. Cupid varieties were popular in the early 1900s and are favourites of North American gardeners. They are classed as container sweet peas and are grown in containers, hanging baskets, window boxes, or on a balcony perhaps. Cupid types have a long history and at one time there were over 30 varieties.

In recent years New Zealand has been the source of new varieties of sweet peas, creating many new colours and fragrances.

The best way of growing sweet peas is from seed. They can be bought as seedlings too, or small plants in cell trays and pots. They are easy to grow from seed, and I have grown them this way ever since I was small. I start them off in three inch (eight cm) pots, sowing one seed per pot. You can also use six inch (15 cm) pots and sow six to eight seeds per pot. There are also sweet pea tubes which have become quite popular. They are ideal, being deep but not wide, which is what sweet peas like.

The usual time to sow is either autumn (late September to early November) or winter (January to February). This does depend on the weather though, as they will not germinate if it is very cold. Sweet peas are surprisingly hardy, but are still best started off in a cold frame.

All I had when I first started gardening was a little cold frame and a shelf in the shed! One of the advantages was being able to grow sweet peas during the winter months. I can always remember rushing down each day after Christmas (I was brought a sweet pea pack for Christmas) anxiously looking for signs of any little green shoots. It was always an exciting time when they appeared.

You can still sow them now, as they will soon catch up. Sowing the seed directly into the ground is an alternative option. This can be done from now until the end of April, but it does depend on the weather conditions of your particular area. Sweet pea seeds are prone to rotting if waterlogged, so a well-drained soil is essential.

I can remember an older friend who grew sweet peas for many years. He always advised me to chip away at the hard outer skin of the seed before sowing, by using a sharp knife or sandpaper. By gently nicking or rubbing the side away from the eye or scar, it is said to shorten the time taken to germinate. I did try this one year and conducted my own experiment where I sowed one pot of chipped seeds and another which I sowed normally. Everything was the same - variety, compost and conditions. I did not notice any difference between the two. They came up at the same time and both grew and performed the same. However, I have read different views and many gardeners do not believe chipping is necessary, so it is a matter of opinion.

Some gardeners soak the seed overnight before sowing and use only those that have swollen, having to soak again until they do swell. I and many other gardeners do believe that this causes stress and that the plants never reach their full potential.

When sowing, a seed and cutting compost or a peat free multi-purpose will be ideal. Water sparingly, keeping the compost moist but not wet, as the seeds could easily rot. Keep them in a cold frame or unheated greenhouse and if frosts are forecast then protect them with sheets of newspaper, taking it off during the day unless the weather is very cold. Make sure you keep your cold frame shut or greenhouse closed unless the weather is warm. Watch out for slugs and snails, mice, and even birds who may take a fancy to your seedlings.

If you have grown them in a cold frame or greenhouse then they should be planted out around April time, but this does depend on when you sowed them and where in the UK you live. You should avoid frosty conditions and the ground must be well prepared before planting. The ground will benefit from adding a little well-rotted manure or suitable fertiliser. I always use some peat-free multi-purpose compost which is mixed in well to create a soft nutritious soil. Heavy soil will need preparing in the autumn as well as the spring, adding the same ingredient mentioned above. It will also benefit from added grit, which will improve the drainage of the soil. Sweet peas do best in a sunny position.

When planting out your seedlings, there are two different ways of planting. There is the cordon method, in which each plant has its own bamboo cane to grow up. These need to be spaced eight to fifteen inches (20 to 38cm) apart, in rows. The second method is the natural way which basically means to let them scramble where they like. This is usually achieved by using pea netting stapled to a fence, or a wigwam of bamboo canes tied with raffia at various points so the tendrils can cling.

Remember to take precautions against slugs and snails, as they can strip seedlings and young plants in a night! I have had this happen in the past and it is very frustrating.

If you have grown the seeds in a cold frame or unheated greenhouse, then the plants will not require any protection against late frosts. However, if the site is very open then it may be worth using mini cloches or even soft drink bottles cut in half to form mini cloches. This may help guard against slug and snail damage, while protecting them a little from icy cold winds. Remove these during the day, unless it is severely cold weather. Hopefully though, the weather should have warmed up when it is planting time.

After approximately 4 to 6 weeks, you should notice them starting to climb. If you are using the cordon method, then you need to restrict the growth to train them up the canes. This is achieved by tying the strongest shoots to the support and pinching off any others which are growing weaker. It is important to check and do this regularly, otherwise the plant will be growing anywhere. However, if you have opted for the natural method then it is important to give them a little bit of help to begin with. This involves tying in the shoots at first by spreading them out over the support. It gives the tendrils a head start in clinging to the support. When the sweet peas start to cover the support, then it will be worth removing some of the shoots to prevent overcrowding.

During warm weather the sweet peas will need checking and watering on a daily basis. Make sure you do not water during the hottest part of the day as this can cause sun scorch. If you prepared your soil thoroughly, then feeding will not be required for a few months, if at all.

Flowers should start to appear from late May to early June. This is when applying a general based plant food is necessary, as the plants need all their energy to put on a lovely display of flowers. Many gardeners (including myself) use tomato food during the flowering period, which helps prolong the blooms.

There are many problems sweet peas can suffer from, but here are the common ones:

• Bud drop - some varieties can be more prone to this than others, but a sudden cold snap can cause flower buds to turn yellow and fall off. It is a common problem in the UK!


• Leaf Scorch - this starts off from the bottom leaves, which causes them to turn yellow and crispy. They may also drop off, which can be quite a shock as it can take hold fairly quickly. To help avoid this, do not water when the sun is at its hottest during the day. There is not a lot else you can do. It does not usually affect the flowers though.


• Aphids - these can be eradicated by using the old method of soapy water in a sprayer, but if the infestation does not get better then a pesticide may be needed. Make sure it is suitable by thoroughly reading the instructions on the packet, or seeking advice in the store. Aphids can transmit a condition called mosaic virus. Plants will have speckled leaves and flowers, which will be poor in growth and stability. Unfortunately the only way to stop this from spreading is to pull out the infected plants and burn.


• Pollen beetles - black insects will be visible inside the blooms, particularly on lighter coloured varieties. Unfortunately there is no control other than placing any flowers which you are using in a display inside a darkened room, with a light source at one end. The beetles will then crawl out and be attracted to the light, which is when you can whip the flowers out. I will leave you to create your own method in getting rid of the beetles from the room!


• Slugs and Snails - these are a pain to many gardeners and can cause major problems to your sweet peas. There are many humane methods used to deter and get rid of some, but I have often used slug pellets sprinkled around the plants which help. Make sure the slug pellets are the kind that are harmless to pets and animals, so it is always important to read the instructions before use.


• Mice - these are a danger to seed during the period of germination. Make sure all cold frame lids are closed at night and greenhouse doors/windows too. There is always a slim chance of them still getting in so keep a careful eye.


• Birds - cover seeds with netting or other suitable material, especially if growing outdoors. I have had birds steal my seeds from pots I had in my cold frame once. If one bird finds them, then he or she will tell their mates so covering them with netting is essential even if you have not had problems in the past.

There is a list of all known current varieties of sweet peas in the online sweet-pea directory.

Growing sweet peas is a fascinating hobby and there are new varieties coming out each year, so you will never be bored with the same ones!

Happy sweet pea growing!!

Nigel's Gardening Hints and Tips
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