Salvia ‘African Sky’

Salvia 'African Sky' (Salvia 'African Sky') is the shrub salvia to plant when a border needs true blue for months rather than weeks. It builds a soft mound about 1.2m tall and 1.2m wide in a single season, then throws up spikes of blue to purple flowers that bees, butterflies and honeyeaters work all day. The foliage is aromatic when brushed.

Why you'll love it

• A long run of blue. Shrub salvias flower across an extended warm season rather than one short burst, so the border holds colour when the roses have finished.
• It fills a gap fast. Fast growing and soft stemmed, it reaches full size in a season, the practical way to furnish a new bed cheaply.
• Drought and heat tolerant. Once the roots are down it copes with dry spells and hot exposed positions, and it takes coastal salt without leaf burn.

Where it works best

Borders and edging. Plant 1m apart along a bed. At that spacing the mounds touch without smothering each other, and the row stays open enough that air moves through, which matters in humid weather.

Mass planting. Blocks of five or more at 1m centres give the best effect, because a single salvia reads as a wispy plant while a drift reads as a wave of colour.

Pots and coastal gardens. A container 400mm or wider suits one plant on a sunny balcony, and it handles salt laden coastal wind better than most soft flowering shrubs.

Growing Salvia 'African Sky' in Australia

Position and climate. Full sun, six hours or more, or the stems stretch and flop. It suits warm temperate, subtropical, Mediterranean and arid to semi-arid gardens. The limit is real: this salvia takes light frost only. In cool temperate and frosty inland gardens it will be cut back or lost over winter, so grow it in a pot that can move under cover.

Soil. Free draining above all else. It grows well on sandy and average soils and does not want a rich bed. On clay, mound the planting position. Wet feet in winter is the usual cause of death.

Water and feed. Water twice a week through the first summer, then only in extended dry spells. A light application of complete slow release fertiliser in early spring is enough, since overfeeding gives fewer flowers.

Pruning. This is the job that matters. Cut the plant back by a third after the main flowering, then harder in early spring to a framework of woody stems.

What to expect when it arrives

It is grown as tube stock and in 140mm pots sold in packs of ten. Tubes are young rooted cuttings, small but quick: planted in spring, a tube is usually flowering by the end of its first summer. The 140mm packs are the sensible way to plant a drift in one go, since this is a plant that looks best in numbers.

Soft stemmed plants travel with a little leaf bruising, which grows out quickly. Water on arrival, keep them sheltered for a few days, then plant into a sunny spot. Delivered Australia wide, with delivery from $29.95, under our 30 day healthy plant guarantee.

Plant care guides and related reading

• Ideas for low growing plants along a border
• Browse plants that attract bees and butterflies
• Compare drought tolerant plants
• Salt tolerant plants for coastal gardens

Common questions

How far apart should I plant them?

One metre apart for a massed display or a border run. Closer planting looks fuller in the first summer but crowds badly by the second, and crowded salvias hold humidity and drop their lower leaves.

Will it survive frost?

Light frost only. A brief touch burns the tips and the plant recovers, but repeated hard frosts in a cool temperate or inland garden will kill it. In those climates use a pot you can shift under cover.

Why has it gone woody in the middle?

It has been left unpruned. Shrub salvias need a hard cut back to a low woody framework each spring.