Liatris: Spiky Purple Blazing Star

Tall, bottlebrush flower spikes set Liatris spicata apart from round daisies and domed perennials like peony or daylily. Those spikes open from the top down, which is the opposite of most spiky flowers.

Unlike many prairie plants that creep aggressively, this one grows from compact underground corms that slowly form clumps instead of runners. That makes it easy to tuck between plants such as coneflower and fine-textured yarrow without it taking over.

Liatris has wiry, upright stems that rarely need staking if it is in full sun. Plants generally reach 2-4 ft tall with a narrow footprint about 12-18 in wide.

It carries narrow, grasslike foliage that stays low and tidy. That grassy texture lets it blend with ornamental grasses or prairie-style mixes highlighted in full-sun perennial designs.

Shorter named varieties solve the problem of tall spikes leaning in exposed gardens. Compact types often top out around 18-24 in, which suits smaller beds or containers better than the classic 3-4 ft species.

You can also find white-flowered forms that read cleaner in moon gardens. White types mix nicely with other white perennials for a cool, evening-friendly color scheme.

Liatris varieties stay fairly close to the wild plant. Differences are mostly in height, flower color, and how tightly packed the flower spikes are.

Full, direct sun gives Liatris the strong stems and dense flowers you want. In less light, it stretches like a tulip in shade, with thinner stems and gaps between the flower clusters.

This plant is happiest with 6-8 hours of direct sun daily. In cooler Zone 3-5 areas, all-day sun is ideal and helps dry the soil after rain.

Farther south where sun is intense, it still prefers open exposure but tolerates a bit of light afternoon shade. That is similar to how many salvias behave in Zone 8-10, taking slight relief from the hottest hours without sulking.

Frequent, shallow watering encourages weak roots, while Liatris performs better with deep, infrequent drinks. Those underground corms store moisture, so they appreciate a soak and then time to dry instead of constantly damp soil.

Unlike thirsty border queens like hydrangea, established Liatris in decent soil can often get by on rainfall alone in many Zone 5-7 yards.

In very sandy sites or drought summers, water about once a week with 1 inch of water until the soil is moist 6 in deep.

Compared with true desert plants discussed in succulent watering tips, it is not a cactus and still needs moisture during active growth. The key is drainage and allowing the top 2-3 in of soil to dry before watering again.

Heavy, soggy clay is the opposite of what Liatris wants; think prairie or meadow instead. The corms prefer well-drained, moderately fertile soil that does not hold water around the roots for long periods.

Unlike heavy feeders such as tomato in the vegetable patch, Liatris does not need rich soil or steady fertilizer. Average garden soil, improved with a bit of compost, usually gives enough nutrients without making the stems floppy.

It handles slightly sandy or gravelly spots well. Raised beds or berms work nicely in wetter climates, much like you might do for raised-bed vegetable beds on poorly drained sites.

Divide crowded clumps first if you want more Liatris that look identical to your best patch. Division gives you flowering-size plants much faster than starting from seed.

Tackle division in early spring as new shoots are just peeking up, especially in colder spots like Zone 3-5 where soil stays wet longer. Cool weather helps roots recover before summer heat kicks in.

Lift the clump with a spade, going in 4-6 inches outside the foliage to avoid slicing through the corms. You will see stacked, rounded corms that look a bit like small, flat bulbs.

Break or cut the clump into pieces with at least 3-5 buds or shoots and a good chunk of roots. Replant divisions at the same depth they were growing, with the top corm 2 inches below the soil surface.

Check Liatris foliage and flower spikes every couple of weeks, but expect far fewer problems than you would see on fussier plants like rose or other high-maintenance flowers. Most years you will not need to spray anything.

Spot aphids first on tender tips and unopened buds, where they gather in soft clusters. They suck sap and can make spikes curl or look sticky from honeydew, which sometimes leads to sooty mold.

Blast small aphid populations off with a strong stream of water in the morning so foliage dries quickly. Repeat water sprays every few days instead of reaching for insecticide right away.

Watch for spider mites in hot, dry summers, especially if nearby plants or containers get them frequently. Mites cause a faint speckling or bronzing on leaves and may leave fine webbing between stems.

Adjust Liatris care a little each season, and you get taller spikes and more blooms without much extra work. The plant behaves like a tough prairie native, especially in Zone 5-8 where it feels most at home.

Start spring by clearing away old stems before new shoots are more than 2 inches tall. Cut last year’s stalks down to the ground and gently loosen compacted mulch so new growth can push through.

Feed lightly in spring if your soil is poor, using a balanced, slow-release fertilizer at about half the label rate. Rich soil that already supports heavy feeders like daylily or other perennials often needs no extra fertilizer at all.

Support tall spikes in early summer only if your site is windy or you grow very tall varieties. A simple ring stake or a discreet bamboo stake tied halfway up is usually all it takes to keep them from flopping.

Support pollinators first by planting Liatris in groups of 5-7 or more so bees and butterflies can find the flowers easily. Spikes open from the top down, giving several weeks of nectar, especially helpful in mid to late summer.

Attract monarchs, swallowtails, and native bees just by mixing Liatris in with other pollinator plants like salvia, yarrow, and other butterfly-friendly flowers. The upright spikes give useful contrast to mounding and airy plants.

Relax about pet safety, since Liatris is not known as a major toxic plant for cats or dogs. If you want extra peace of mind, you can focus high-chew areas on non-toxic options like pet-friendly houseplants and keep Liatris in outdoor borders.

Avoid overplanting beyond your yard’s boundaries if you live near sensitive natural areas, even though Liatris is native to much of eastern North America. Work with local species lists, just as you would when choosing shrubs like ornamental hydrangeas for woodland edges.