Gardening: Use big leaves to break up your borders

Stunning purple of Angelica gigas purpurea.
Stunning purple of Angelica gigas purpurea.

The best piece of advice I’ve ever read about designing borders came from Beth Chatto – if you want success, look at the size of your leaves.

If there’s nothing bigger than a privet leaf, it will look bitty – break it up with big-leaved beauties.

Unsettling shape of the ornamental rhubarb flower head!

Unsettling shape of the ornamental rhubarb flower head!

The eyes will pause at these ‘full-stop’ plants before carrying on to take in the rest.

Big-leaved plants look exotic and hard to look after but these ones aren’t. I absolutely love them, to the point that I may have too much punctuation and not enough words in my borders!

They are all herbaceous perennials, apart from the Angelica and Verbascum, which are biennial:

Rheum palmatum (ornamental rhubarb) - From a brown crown in spring, the green leaves with purple undersides sprout from purple buds to produce a cream flower spike 8ft tall by June. Very impressive, especially near water, but plant something in front as the lower leaves get raggy as summer progresses.

Rodgersia: Green/bronze pinnate leaves grow from a spreading crown. Elegant spires of cream/pink flowers in early summer. Goes well with the ornamental rhubarb.

Acanthus mollis (bear’s breeches): Handsome shiny green leaves that are almost evergreen, except in bad winters. Leaves copied to form the capitals of Corinthian columns in antiquity. Purple and white hooded flowers, growing to approx 5ft.

Globe artichoke/cardoon (Cynara cardunculus): The pair are closely related and look much the same, with large dissected, silvery foliage, rising to large, thistle-like edible flower buds/heads about 8ft high.

Angelica: Large bipinnate leaves, growing from 3-9ft, depending on variety.

Most usually grown is bright green herb Angelica archangelica, from which the young stems can be candied. A. atropurpurea, the purple form, is also popular. Umbels of white/green/pink flowers in summer. biennial, but self seeds.

Verbascum bombyciferum (giant mullein): Its silver, furry leaves form a rosette 3ft across and in its second year, a huge flower spike erupts, carrying a yellow candelabra of blooms up to 8ft. A show stopper!

Hostas: Big Daddy (30”), large corrugated blue leaves (15”x10”), cupped and almost round with off-white flowers. Blue Mammoth (34”), puckered blue leaves (16”x12”), near-white flowers. Empress Wu (50”), huge dark green leaves (28”x25”), pale lavender flowers.

Ferns: My favourite is the shuttlecock, or ostrich fern. In spring, lance-shaped, sterile fronds are produced in regular ‘shuttlecocks’ up to 5ft tall, followed in mid and late summer by smaller, more erect, darker, and longer-stalked fertile fronds, which persist over winter.

JOBS TO DO THIS WEEKEND

Plant out cannas (pictured) and dahlias when danger of frost is past. Tubs can be planted up with summer bedding,but make sure the plants are hardened off and keep fleece handy in case there’s a cold night.

Sow French beans, runner beans, squash, cucumbers and pumpkin seeds directly into prepared beds outside. Be alert to late frosts (horticultural fleece should provide enough protection).

If you want to grow spring bedding, wallflowers, pansies, and daisies need to be sown between now and July to flower next spring.

Keep tubs, hanging baskets and alpine troughs well watered. Use collected rainwater, or recycled grey water (from the bath).

Remove dead leaves from around the basal rosettes of alpine plants to prevent rotting. Top dress spring-flowering alpines with grit or gravel to prevent rotting around the neck.

Clip evergreen hedges. If not too woody, shredded clippings can be added to the compost heap.

Prune overcrowded, dead or diseased stems of Clematis montana once it has finished flowering.

It will take even hard cutting back very well.

Apply a high nitrogen summer lawn fertiliser to encourage a healthy-looking lawn, taking care to avoid any runoff.

Continue to plant up bog gardens.

Self-blanching celery can also be planted out.

Thin gooseberries if you want large fruit.

Start to remove sideshoots from cordon tomatoes as you see them. The sideshoots develop in the leaf axils (between the stem and leaf), and if allowed to develop will reduce the quality of the yield.

GET IN TOUCH

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