Coral Bells Heuchera Fire Alarm

Bright brick red foliage is the entire point of Fire Alarm. The leaves are rounded and lobed with a lightly ruffled edge, held in a low evergreen mound, and the colour runs hottest on new growth and through the cooler months before easing towards bronze as summer heat builds. Thin stems of small bells appear, but they are a footnote beside the leaves. It is grown for colour in positions that get no direct midday sun: shaded borders, path edges, and as the bright element in an otherwise green pot.

Humid summers are the test

Fire Alarm is easiest in Melbourne, Adelaide, Hobart and the southern tablelands, where summers are drier and the nights cool off. In Sydney and up the coast it needs help. Give it part shade with morning light, moderate water, and a bed lifted with compost and coarse grit so water never sits around the roots. The failure mode is a still, humid summer. Heucheras planted in a sheltered pocket with no air movement, crowded against a fence or under dense evergreen cover, collapse from the middle in February: leaves go limp and brown from the centre out and the whole crown follows within days. Air movement is the fix, and it matters more than the depth of the shade. Space plants at least 300mm apart, keep them away from the base of walls where warm air stagnates, water the soil rather than the foliage, and clear fallen leaves off the crown through the wet months. In a pot, raise it off the ground so the base drains freely instead of standing in a wet saucer.

Which warm toned coral bells

The closest thing in this batch is Marmalade, and the choice between them is climate rather than colour. Marmalade comes from the hairy leaved villosa side of the genus and holds up better through warm, humid summers, so it is the safer buy in Brisbane or coastal Sydney; Fire Alarm gives a cleaner, brighter red but wants the cooler, drier conditions of southern gardens. If you want a red that stays constant instead of shifting to bronze over summer, Forever Red holds its wine tone all year. Fire Alarm is for gardeners who actually like the seasonal swing. See the full coral bells range.

Tidying, feeding and resetting the crown

There is no pruning as such. Pull or snip tired outer leaves off at the base as they fade, and cut the flower stems out once they finish, since they add little here. Feed lightly in early spring with a slow release complete fertiliser and again once the worst of the summer heat has passed; heavy feeding gives soft, floppy leaves that scorch and rot more readily. Over a couple of years the crown lifts itself out of the soil on a woody neck and dries out. Lift the plant in late winter, trim the old stem, and replant it deeper. Snails and slugs will lace new growth in spring.

Choosing a size

This plant is supplied in one size, 140mm, at $16.95 per plant. The size shown is the pot it arrives in, which is the rootball, not the height of the plant. Not sure which to choose? Read our guide to when to plant in Australia.