Licorice Plant Helichrysum Petiolare (Helichrysum petiolatum)

Licorice plant is grown for foliage alone: rounded, densely felted leaves in soft silver grey, carried on long lax stems that sprawl and trail rather than climb. It is a South African sub-shrub, woody at the base and loose everywhere else, and the small dull cream flowers it throws are worth cutting off. Designers reach for it to soften a wall edge, spill from a pot or basket and cool hot flower colours, and one plant covers far more ground in a season than its pot size suggests.

Gritty soil, moving air, and rot in a wet summer

It suits Mediterranean conditions and dislikes anything close and muggy. Give it gritty, free draining soil, ideally on a slope, a raised bed or the top of a wall where water runs away from the crown, and leave air moving around it rather than crowding it with neighbours. The failure mode is rot: those woolly leaves hold water, and through a humid summer or in a poorly drained bed the stems blacken and whole sections collapse at once. Thinning the growth in midsummer to open it up does more good than any spray. Allow real room when planting, because it will smother a smaller neighbour inside a season. One responsibility comes with it. Helichrysum petiolare has naturalised in parts of cooler southern Australia and it strikes readily from stem pieces, so bag prunings for green waste rather than tipping them over a back fence, into a bush corner or onto a creek bank. It strikes so readily from cuttings that most gardeners replace a collapsed plant from their own material rather than nursing an old one through a second wet summer.

Silver that trails against silver that holds a shape

Set it beside cushion bush, the other silver here, and the difference is structural. Cushion bush is a rigid, self supporting ball of white stems that will not regrow from bare wood, so it is trimmed lightly and eventually replaced. Licorice plant is soft, quick and floppy, tolerates being cut back hard into old wood, and is the one to choose for spilling over an edge or filling a basket in a single season. If you want a spiller that flowers rather than one grown purely for leaf, seaside daisy does that job in the same dry, exposed positions. Neither of them belongs in a bed that stays damp, and the only difference is how quickly each one tells you about it.

Cutting it back hard, and going light on fertiliser

Light trimming is the wrong approach with this plant, since it only adds density where you want air. Cut it back hard instead, taking it back by half or more in early spring before the new flush, and again after midsummer if it has run over its neighbours. It breaks readily from old wood, so a severe cut is recoverable. Remove flowering stems as they appear if you want the foliage to stay dense. Feed sparingly or not at all: rich soil and regular fertiliser give soft, sappy growth that flops open, loses the silver density and rots at the first humid week.

Choosing a size

This plant is available in 2 sizes, from 130mm up to 180mm, priced from $16.95 to $22.95 per plant. The size shown is the pot the plant arrives in, which is the rootball, not the height of the plant. These are younger plants, priced for planting in quantity, and they establish quickly once in the ground. Not sure which to choose? Read our guide to when to plant in Australia.