PUBLISHED: 12:00 17 August 2015
Plant specialist Keith Clouting, from Taverham Nursery Centre, brings you his guide to getting the best out of your garden.
One of my favourite plants of high summer is the Californian tree poppy (Romneya coulteri). At this time of year it has upright branching stems to around 2m tall, with divided, intensely glaucous, grey-green leaves. For a long period through the summer the stems are topped by large buds which open into beautiful, crinkled, pure white flowers, 15cm across with a mass of prominent yellow stamens in the centre. R. coulteri prefers well-drained soil in a sunny, sheltered position. They resent disturbance and can be a little slow to establish, but once settled can spread rapidly. Mulch well in winter, then in spring cut back the stems low down to form a framework from which the new growth will shoot.
Another plant which really shines this time of year is the Penstemon. There is a bewildering choice of varieties available but some of the older stalwarts still stand out. One of the best performers for me is P. Alice Hindley which produces stems to around 90cm and with deadheading produces its tubular-shaped mauve flowers flushed with white all summer and into autumn.
A lower-growing variety and one of the most colourful is P. heterophyllus Heavenly Blue. Parent of many hybrids, this cultivar is an excellent choice for the edge of a sunny border or rockery. It produces its rich mauve-blue flowers for months on stems to around 45cm high. Penstemons thrive in well-drained soil and full sun - they can be grown in partial shade but flowering will be reduced. Leave growth on throughout the winter to help protect from frost, then in spring prune to around 15cm to encourage a bushy plant. Penstemons also attract many beneficial insects and are resistant to slugs and other pests.
Plant of the month
Liatris spicata Kobold
This cultivar of a prairie plant from the United States forms a low clump of grassy-like foliage. From midsummer it produces spikes of fuzzy-looking bright purple flowers which are attractive to butterflies and bees. This compact form reaches 60cm high with a spread of around 45cm. It’s happiest in full sun in most good garden soils, combining well with other perennials and grasses.
Catch up with Keith
Thin out swelling bunches of grapes to get the largest, tastiest grapes.
Raise the height of mower blades to help lawns to cope with any hot dry spells.
Cut back herbs to encourage a new crop of fresh leaves before winter.
Hedges can be given their final trim of the year.
Taverham Nursery Centre,
Fir Covert Road, Norwich;