Every year I try to grow something new and I do have a bit of a thing for the Solanum family (Solanaceae). I have grown the prickly Solanum sisymbrifolium before but never dared eat the fruit so thought I would give it another try this year. Because the Chiltern Seed catalogue listed several others I thought I would try Solanum pyracanthum (also listed as S. pyracanthos and S. pyracanthon) too for a change. Both are frost-tender perennial shrubs but can be grown as annuals. My S. pyracanthum are still small but they are already fascinating and beautiful.
After the disaster early in spring when I lost a lot of seedlings I had to sow this again and without heat but the seedlings still appeared within three weeks in April. Though slow to get going the young plants, now in 10cm pots, are growing strongly and although there are no flowers the plants have a lot going for them. The leaves are felted grey and attractively lobed but it is the prickles on them that are the real ‘wow’ factor. The midribs of the leaves are golden orange and along them are thick, stout, prickles of the same colour, shaded purple at the base. They are more or less symmetrically arranged across the leaves and also thickly up the stems. Solanum pyracanthum is also known as the porcupine tomato and is native to Madagascar. There are 1500 species of solanum and the number keeps increasing as more species are added, including the tomato which used to be Lycopersicum esculentum. The porcupine tomato has pretty purple flowers and should reach at least 1m high though I have seen reports of it getting three times that. In warm (frost-free) climates it may become a weed but I think this is doubtful here. The small fruit are reportedly edible but not very good eating but I will grow this purely for its ornamental value.
Solanum sisymbrifolium is more familiar to me and I think it should be more widely grown. Although the prickles are less beautiful and are more annoying than ornamental, being profuse but not so showy, the flowers are really pretty. Sown at the same time as S. pyracanthum, the plants are much taller, already 30cm high and most are in flower, with terminal clusters of bloom. The flowers are quite large (about 3cm across) and almost white with a lilac flush. They open fully during the day but close at night. This is sometimes called the Lychee tomato and has bright red fruits that are partly enclosed in the five spiny sepals. I have never had the courage to eat them but will give them a try this year.
So far the plants are in the greenhouse but I will plant some out and keep some inside. I have grown it outside before and it has made a large, bushy plant 1m high in the past although it usually needs staking to keep it upright.
I am also growing some wonderberries, ground cherries and tomatillos this year, all closely related to solanums and I will post on these as well as the above solanums as they start to do their thing!
Other useful and better known solanums
S. capsicastrum Winter cherry – ornamental
S. crispum Potato vine – ornamental
S. laxum -ornamental
S. lycopersicum Tomato
S. melongena Aubergine
S. tuberosum Potato
S. rantonnetii Potato bush – ornamental
S. nigrum Black nightshade – weed
S. dulcamara Woody nightshade – weed/ornamental
S. muricatum Pepino (my seeds did not germinate this year)