Rhodiola rosea is also called golden root or rose root, and is sought-after for its use as an herbal remedy in holistic medicine, but as far as gardening goes, it can be a tricky plant to grow outside its native climates, which are sub-Arctic and cold. It’s possible to grow this plant, which is a type of stonecrop, in Kansas, with the right conditions. Kansas is split between cold hardiness zones 5 and 6, which is on the warm end of climates Rhodiola rosea can grow in.
Choose a good spot to plant Rhodiola rosea. Despite its cold origins, it cannot survive in the shade and needs plenty of sun. Partial shade during the hottest part of the day is OK, but choose a spot with at least eight hours of sunlight.
Dig a planting spot. Rhodiola is hardy and can tolerate many kinds of soils, but it must be well-drained. If your soil is thick and compacted, dig up the planting spot to a depth of 1 foot. If it is already well-drained, simply rake up the top 1 inch or so, as rhodiola has shallow roots.
Amend the soil, if needed. Kansas soils typically are some variety of loam, which may already be well-drained and mixed. But if you have heavy soil and need better drainage, mix the turned soil with one-third sand and one-third peat moss or perlite.
Plant Rhodiola rosea early in a Kansas spring; late March or early April. It germinates at fairly cold temperatures, around 50 degrees F, so early spring is the right time. It’s OK if you plant it before your area’s last frost date, as the seeds are frost-hardy.
Plant Rhodiola rosea seeds about 1 foot apart if you want to use it as ground cover. The plant reproduces quickly, so plenty of room is a good idea. Plant them by scattering on the surface and covering very lightly with a sprinkle of soil, just enough that they don’t blow away.
Keep seeds moist, until seedlings sprout. In dry soils, spread a layer of wet compost or mulch on the top before planting to keep moisture near the seeds.