Lobelia tupa is a giant of a plant, very tropical in appearance, growing to a height of between fourand six feet tall with a similar spread.
This lovely plant has pale green felted leaves and scarlet red flowers. It has an inoffensive running habit and likes to colonise fresh ground from year to year. Do not try to contain, let it roam. The flowers are produced on long spires up to 18 inches long from mid summer to mid autumn. The plant is a native of Chile and will not tolerate temperatures below –10 degrees Celsius. Cover the plant with a mulch of leaves or compost over the winter months. Plant it in a sunny position or light shade in an open position with shelter from wind. It likes a moist soil enriched with well rotted manure or compost. The plant can be propagated from seeds sown from February to March. Germinate the seeds at 10-15 degrees Celsius on the surface of a good free draining damp peat/sand mix compost, do not cover the seeds, light is beneficial at this stage for germination. Place the tray of seeds in a propagator or sealed inside a polythene bag until germination has occurred which usually takes 14-30 days.
Lobelia is a plant also used to fill hanging baskets or for edging a flower border. Lobelia cardinalis is a short-lived moisture loving plant with green leaves and a display of bright red flowers from July to August. Many other colourful forms have been bred from this plant. Lobelia cardinalis ‘Queen Victoria’ with its dark, almost black, foliage and red flowers is one of the true stars.
Another herbaceous plant to enjoy at this time of the year is Gaura ‘Crimson Butterflies’. A native of Australia the plant has bronze foliage and produces spires up to 2 feet tall which are covered with crimson flowers. The flowers have a short life in wet weather, like this summer. Grow the plant in moist, fertile well-drained soil in full sun. Gaura lindheimeri is a slender clump forming perennial from Texas. The flowers are produced above the foliage on erect spires up to 2 feet tall. These spires continue to grow throughout the flowering period, which can extend from late spring to early autumn. The individual flowers have four petals and are white when they open in the morning, fading to rose-pink in the evening. Only a few flowers are open at any one time and each flower drops off after blooming to leave a neat, clean stalk. The plant can tolerate drought and shade because it has a long tap root.
Indigofera heterantha (also called Indigofera gerardiana) is a deciduous shrub that flowers from summer into the autumn. The plant produces arching branches, with elegant, pinnate grey-green leaves and masses of pea like purple-pink flowers. It can grow up to ten feet tall in a moderately fertile, moist but well drained soil in full sun. It can be grown in a shrub border or trained against a warm, sunny wall.
Eucomis or pineapple plant is a tender plant from South Africa. Eucomis is only winter hardy in frost free or warm gardens. It is very suitable as a pot plant that is brought indoors for the winter in frost-prone gardens. Grow the plant in a fertile, well-drained soil in full sun in a sheltered position at the base of a warm wall and mulch in winter. The bulbs look better when planted in a group rather than left to grow singly. The flower spike produced in late summer and early autumn is an amazing sight. Each spike can range in size from 12 to 24 inches tall and is made up of hundreds of small flowers that open from the bottom up. The top of the flowering spike has a turf of green leaves, similar to those found on a pineapple, hence its common name the pineapple lily. Eucomis bicolor has pale green leaves with a purple margin to the petals.
Jobs for the week:
Prune wisteria, cutting the long stems back to three or four leaves from the main stem. If the plant did not flower well this year give it a feed of high-potash fertiliser.