Perovskia atriplicifolia ‘Blue Spire’ (Russian Sage)

This one looks delicate, but it’s hard as lilac-tinted nails. Also a holder of an RHS award for Garden Merit and these are not chucked about willy-nilly so we’re really keen on this one.

It’s bushy but open-formed with ever so fine-spun stems and diddly little leaves that are silvery-green. These make fine bedfellows (nice dry beds, please) for other such greyish plants like Lavenders in dry landscapes or Mediterranean garden designs. Plant loads of them in drifts if you can, they look super this way. Also especially striking when combined with clumpy mounds of grasses, of any shade.

We’re generally happiest when up to our necks in structural shapes, balls and blobs but you do need some puffs of not-shapes to bring it all together. Think of ‘Blue Spire’ as an edge-less, smoky sort of a not-shape that will soften edges and blur boundaries in a rather dreamy way.

In August and September this not-shape will be an absolute heaving mass of teeny blue flowers held on white stems above their silvery green leaves, making heavy clouds of purply cigar smoke that will attract admiration and a lot of bees. Though it is deciduous and will die back to ground-level in winter, it will re-grow reliably every year up to around 1.2 x 1.0metres.

We said it was tough and it is. From the dry plains of central Asia, this plant flourishes in full sun on well drained, dry and chalky soils, in either exposed or sheltered positions. Keep it away from the coldest of cold north winds though. Final bonus: it will even tolerate salty air. That award is looking shiny, isn’t it?

N.B. When clipping several plants with the same tool, have a bucket containing a 5% bleach solution and swish your blades around for 30 seconds between plants to sterilise them. This will help avoid the chance of cross contamination of disease.

As with all woody plants, plant high, exposing as much of the taper at the base of the trunk as possible. Allowing soil to accumulate round the base of a tree can be fatal. Keep very well-watered when first planted.