Choosing Acid Loving Plants - Perennials and Climbers

Gentiana sino-ornata (Gentian)

Form:

herbaceous perennial

Foliage:

deciduous

Hardiness:

UK - hardy; USDA zones 5 to 7

Soil:

moist acid soil

Situation:

sun

Height:

7cm (3in)

Spread:

30cm (12in)

Awards:

RHS AGM

Reasons to grow: Bright green mats of foliage smothered in intense azure blue, trumpet shaped flowers from early autumn to early winter. This little plant looks stunning at the front of borders or planted among paving stones. A real gem amongst acid loving plants!

Iris pseudacorus 'Variegata' (Flag Iris)

Form:

perennial rhizome

Foliage:

evergreen except in the coldest winters

Hardiness:

UK - hardy; USDA zones 5 to 8

Soil:

deep, permanently moist, humus rich acid soil

Situation:

full sun or partial shade

Height:

75-90cm (30-36in)

Spread:

45cm (18in)

Awards:

RHS AGM

Reasons to grow: One of the very best acid loving plants for a waterside location as the creamy white striped sword shaped leaves provide architectural form. Each stem produces four or more bright yellow flowers from mid to late summer.

It can be invasive so if space is restricted remove the seed heads after flowering or grow in containers sunk into the ground. See important note below.

Also consider: Where space is limited try growing I. ensata; for drier conditions try I. sibirica.

Important note: Iris pseudacorus is native to Europe, the British Isles, North Africa and the Mediterranean where it grows both in the wild and as an ornamental. Outside these areas, and certainly in the US and Canada, it has escaped from cultivation and poses a threat to native eco-systems. In many of these regions it is classed as an invasive aquatic plant and should not be cultivated.

Liriope muscari (Big Blue Lily-turf)

Form:

perennial

Foliage:

evergreen

Hardiness:

UK - hardy; USDA zones 6 to 10

Soil:

well-drained, neutral to acid soil

Situation:

partial to full shade, but will tolerate a sunnier spot if the soil is reliably moist

Height:

30cm (12in)

Spread:

45cm (18in)

Awards:

RHS AGM

Reasons to grow: An excellent and hard working plant. From August to November, as other flowers are beginning to fade, spikes of deep violet flowers rise above the dense strap-like foliage.

This tough little plant will cope with difficult conditions including dry shade and drought and makes excellent groundcover.

Meconopsis betonicifolia (Tibetan Blue Poppy)

Form:

clump forming perennial

Foliage:

deciduous

Hardiness:

UK - hardy; USDA zones 7 to 8

Soil:

reliably moist but well drained, rich acid soil

Situation:

partial shade sheltered from wind

Height:

1.2m (4ft)

Spread:

45cm (18in)

Awards:

RHS AGM

Reasons to grow: Large, delicate, saucer-shaped blue flowers unfurl magically from the drooping buds in early summer. Although it isn't perhaps the easiest plant to grow, this is one of those acid loving plants that stops you in your tracks when it is flowering.

Also consider: M. grandis for larger but less clustered flowers; M. x sheldonii, a hybrid of M. betonicifolia and M. grandis.

Campsis x tagliabuana 'Madame Galen' (Trumpet Vine, Trumpet Creeper)

Form:

climber

Foliage:

deciduous

Hardiness:

UK - hardy; USDA zones 5 to 9

Soil:

any moist to well drained, tolerant of acid soil

Situation:

sunny sheltered site

Height:

10m (33ft)

Awards:

RHS AGM

Reasons to grow: A bold vigorous climber bearing exotic trumpet shaped orange red flowers in profusion from late summer to autumn. Excellent for Mediterranean style gardens and wall side borders.

Although it is tougher than it looks, it may need some winter protection for the first couple of years.

Hedera colchica 'Dentata Variegata' (Persian Ivy)

Form:

self clinging climber

Foliage:

evergreen

Hardiness:

UK - hardy; USDA zones 6 to 9

Soil:

although best in fertile, humus-rich, alkaline soil it will tolerate acidic soils

Situation:

sunny sheltered site

Height:

up to 8m (26ft)

Spread:

up to 4m (13ft)

Awards:

RHS AGM

Reasons to grow: A vigorous self clinging climber with large handsome heart-shaped leaves with a broad, creamy-white margin. Excellent for covering a shady unattractive wall and also effective as groundcover.

Also consider: 'Sulphur Heart' for dark green leaves suffused with yellow.