Dwarf sweet peas - Small yet perfectly formed


March 2002

    Dwarf sweet peas have thrown off the problems of the past and become extremely useful and attractive garden plants. Graham Rice traces their development and suggests we take a fresh look at these underrated annuals

If a sweet pea that never needs staking sounds like a great idea, that’Äôs because it is. These sweet peas that do not need support can be superb garden plants, especially for those of us without the time to erect canes and tie in stems regularly.

Some gardeners dismiss them because the flower stems are not long enough to cut for arrangements and the scent is a little variable throughout the group. Discard any prejudice and look at these dwarf sweet peas for what they are: invaluable neat and prolific plants that have been proven by the many awards received over the years. They make fragrant mounds of colour in beds and borders, and provide a different element for containers and hanging baskets.

For practical purposes dwarf sweet peas (cultivars of Lathyrus odoratus) can be defined as being 30cm (12in) or less in height. They achieve this compact habit because the stem length between the leaves (internodes) has been shortened; a mature plant may have as many leaves as a traditional sweet pea but these may be only 2.5cm (1in) apart rather than 15’Äì20cm (6’Äì8in). Their leaves are noticeably in proportion; the flowers, too, are smaller and on much shorter stems. The result is a neat mound covered in blooms.

Origins

The first cultivars that grew discernably shorter than traditional sweet peas were noticed in the USA around 1850 (see notes) in the era of the Grandiflora types, or ’Äòold-fashioned’Äô sweet peas. For 25 years, a quarryman’Äôs wife in New York state (ie not in the city) grew the pretty old pink-and-white bicolour ’ÄòPainted Lady’Äô on her shallow and stony limestone soil. Every year she saved seed and over the years her continual selection meant her sweet peas evolved to be noticeably more compact. Her cultivar was introduced in 1889 as ’ÄòBlanche Ferry’Äô.

A much more startling development took place in 1893. In California, among rows of ’ÄòEmily Henderson’Äô, the best white sweet pea of its day, and itself a descendant of ’ÄòBlanche Ferry’Äô, a single white-flowered plant was found that grew only a few inches high. This new sport proved amazingly consistent, and it was sold to W Atlee Burpee, the largest American seed company of the time, who named it ’ÄòCupid’Äô.

In that year another sport was found in ’ÄòBlanche Ferry’Äô ’Äì a pink and white counter-part of ’ÄòCupid’Äô. Burpee paid $1,500 for the entire stock of 1,068 seeds, surely the highest sum ever paid for a sweet pea at the time, and introduced it in 1898. A ’Äòyellow’Äô sport (in fact cream) was then found in ’ÄòCupid White’Äô and introduced in 1899 as ’ÄòCupid Primrose’Äô.

There followed a rapid flow of ’ÄòCupid’Äô cultivars and soon most (cut, cumsy: of a wide range of intense colours of) of the many colours already found the Grandifloras were available, with 31 being introduced in just a few years. However, there was a problem. Germination of the first white-flowered ’ÄòCupid’Äô was poor and, in spite of all the extensive breeding work, gardeners were disappointed. By 1914, Burpee had cut back to just a white, a pink and a mixture.

Revival

With the rising number of small gardens in the 1950s there was a serious attempt at a revival and 10 Cupid-type cultivars gained RHS awards following trial at RHS Garden Wisley. The Cupid mixture was listed for a few years, but soon faded away. Over the years, new cultivars in the same style have appeared; ’ÄòBijou’Äô, ’ÄòFantasia’Äô, ’ÄòPatio’Äô and ’ÄòLittle Sweetheart’Äô are still found in catalogues. Occasionally, some of these have received awards, but consistency and availability of seed stock continue to present problems.

Now there is another revival of this type. The germination problem of ’ÄòCupid White’Äô has been solved, seedlings of ’ÄòCupid Pink’Äô ’Äì which received an Award of Garden Merit (AGM) in 1995 ’Äì have flooded into garden centres, and new colours are appearing from a number of British and overseas sources.

Modern Cupid types are again available under that name, and 11 colours have been bred in Britain by crossing ’ÄòCupid Pink’Äô with other dwarf sweet peas to develop a range of prolific, stable colours. Also bred in Britain, the Pinocchio Series is similar in style, also prolific and available in eight colours, one with an AGM. All colours are scented and there is more emphasis on striped flowers. Recently introduced ’ÄòLavender Bridesmaid’Äô agm (syn. ’ÄòTeresa Maureen’Äô) is white with pretty purple markings and especially strongly scented. As with ’ÄòCupid Pink’Äô, it is gorgeous when simply used to fill a container on its own.




Revival

With the rising number of small gardens in the 1950s there was a serious attempt at a revival and 10 Cupid-type cultivars gained RHS awards following trial at RHS Garden Wisley. The Cupid mixture was listed for a few years, but soon faded away. Over the years, new cultivars in the same style have appeared; ’ÄòBijou’Äô, ’ÄòFantasia’Äô, ’ÄòPatio’Äô and ’ÄòLittle Sweetheart’Äô are still found in catalogues. Occasionally, some of these have received awards, but consistency and availability of seed stock continue to present problems.

Now there is another revival of this type. The germination problem of ’ÄòCupid White’Äô has been solved, seedlings of ’ÄòCupid Pink’Äô ’Äì which received an Award of Garden Merit (AGM) in 1995 ’Äì have flooded into garden centres, and new colours are appearing from a number of British and overseas sources.

Modern Cupid types are again available under that name, and 11 colours have been bred in Britain by crossing ’ÄòCupid Pink’Äô with other dwarf sweet peas to develop a range of prolific, stable colours. Also bred in Britain, the Pinocchio Series is similar in style, also prolific and available in eight colours, one with an AGM. All colours are scented and there is more emphasis on striped flowers. Recently introduced ’ÄòLavender Bridesmaid’Äô agm (syn. ’ÄòTeresa Maureen’Äô) is white with pretty purple markings and especially strongly scented. As with ’ÄòCupid Pink’Äô, it is gorgeous when simply used to fill a container on its own.

In the garden

But it is not only in containers and baskets that these pretty little annuals are effective. I have grown them at the front of mixed and annual borders where they work well. ’ÄòCupid Pink’Äô, still the most popular colour, nestles prettily among the dark wavy foliage of Heuchera ’ÄòChocolate Ruffles’Äô, or the dark crimson foliage of Solenostemon ’ÄòRob Roy’Äô (coleus) in a scheme of summer annuals. ’ÄòSweetie White’Äô looks delightful tucked under the front of a white-edged hosta such as H. ’ÄòFrancee’Äô, while the sultry shades of ’ÄòPinocchio Carmine and White’Äô sparkle in front of purple-leaved sedums or interplanted with Veronica peduncularis ’ÄòGeorgia Blue’Äô.

With such combinations in mind, and the lure of pots and hanging baskets overflowing with fragrant blooms, once again gardeners can appreciate these dwarf sweet peas as fine garden plants in their own right. No longer need they be regarded as a so-far unrealised dream. Dwarf sweet peas are now, rightly, seen to be good.

Growing in containers

Dwarf sweet peas work well when grown in containers and hanging baskets without companions, either as specimens in single colours or in a carefully selected blend of separate shades. ’ÄòCupid Pink’Äô, ’ÄòSweetie White’Äô and ’ÄòSweetie Salmon’Äô, for example, would make an attractive partnership.

The Sweetie Series were selected for their value as hanging basket plants, having a dwarf, semi-trailing habit and coming in six different colours, all of which have some scent. Alternatively, sweet peas can be grown in carefully planned schemes with other plants. Choosing companions for these dwarfs requires a little thought.
To add colours other than those of dwarf sweet peas consider the following plants, which are roughly in the right scale:
Viola ’ÄòMagnifico’Äô (blue-edged white flowers)
Anagallis ’ÄòSkylover’Äô (small, brilliant blue flowers)
Brachyscome ’ÄòLemon Mist’Äô (yellow daisy flowers)
B. multifida (mauve daisy flowers)
Scaevola ’ÄòSaphira’Äô (blue flowers and neat habit)
Petunia Million Bells Lemon (’ÄòSunbelki’Äô) (better than the trailing Million Bells types which hang down in a curtain)
Helichrysum petiolare ’ÄòGoring Silver’Äô (trailing, less vigorous than other helichrysums)
Trailing antirrhinums (particularly yellow)
Lantanas
Suteras in the newer fiery shades.

Raising dwarf sweet peas

Dwarf sweet peas can be sown in the open garden, where they are to flower, but are usually better raised in pots. In March or April, soak seeds overnight on damp kitchen paper, chip any that fail to swell with a sharp knife, then sow three or four seeds to a 9-cm (3-1/2in) pot. Seedlings do not require pinching after germination as they branch naturally. When they are about 7.5cm (3in) high, plant out in containers or in any good soil, anywhere which is sunny for at least half the day.

Sources

Suttons Seeds, Woodview Road, Paignton, Devon, TQ4 7NG (01803 696321)
Plants of Distinction, Abacus House, Station Yard, Needham Market, Suffolk, IP6 8AS (01449 721720)
Unwins Seeds, Histon, Cambridge, CB4 4LE (01223 236236)



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All text ©copyright Graham Rice 1999-2006, All images ©copyright Graham Rice/gardenphotos.com or judywhite/gardenphotos.com 1999-2006.
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