The garden nasturtium is usually grown from seed and dies in late autumn. Its low maintenance and attractive flowers have long made it a favourite.
In addition to the varieties that come in either red or yellow, there are bicoloured forms with more unusual streaked and blotched petals.
The smooth leaves are shaped rather like shields, held on thin stalks about 10cm long. They come in all shades of pale and bright green, and some are marbled or splashed with cream.
Ideal situation
Many varieties of the garden nasturtium have a climbing or trailing habit. Although they can reach a length of over 3m, they will be much shorter if you confine the roots to a small tub, window-box or hanging basket. The stems will still cascade down the sides of the container, making the most of their growth habit.
If you grow trailing nasturtiums in a flower-bed, they need some kind of support to grow up, such as bamboo canes or trellis.
You can plant the more vigorous trailing varieties in groups to scramble down a bank, twine through a hedge or wind their way round the trunk of a tree.
POPULAR VARIETIES
'Alaska': Marbled or striped, pale green and cream leaves with bright yellow, orange and red flowers held well above the foliage. Grows to 20cm. 'Tip Top': Large, single flowers in apricot, scarlet, mahogany and gold; bright green foliage. Height ranges from 25-30cm. This variety is sold in packets either of single, named colours or as a mixture.
'Tom Thumb': Dwarf, up to 15cm tall. Its compact, bushy growth is useful in a small garden. Flowers in a wide range of colours. Double `Gleam' hybrids: Semi-trailing, they are good varieties to grow in pots for planting up window-boxes and hanging baskets; scented, semi-double flowers in a mixture of yellow, gold, orange and scarlet. Grow to 30-40cm.
BUYING TIP
Buy trays of seedlings for planting out during the late spring and early summer, or buy packets of seed. This plant is one of the easiest annuals to grow from seed. Sow seed at room temperature in trays or pots in early spring or directly into the soil where the plant is to flower after all danger of frost has passed.