hodiola Rosea can be cultivated in two ways - from seed, or by vegetative propagation.

Cultivation from seed
The seeds of Rhodiola Rosea are very small (about 1.5 - 2mm long by 0.3 - 0.6mm). Growing from seed can be difficult, because the dried seeds have a low germination capacity (only about 2 - 25% of them will germinate). However, this can be improved if, prior to planting, the seeds are stored in moist sand in cool conditions for about a month. (The dry seeds are soaked in water overnight, then mixed into moist sand and kept in a suitable container). After storage for one month at a temperature between 0 - 2°C, the germination capacity will typically increase to around 75%. And by using natural stratification, sowing outdoors in the autumn (during September-October), it is possible to achieve 95-100% germination. After planting (see below), the seeds sprout after 4 - 5 days and the first leaves appear in 25 - 40 days.

Vegetative propagation (root division)
Rhodiola Rosea can also be propagated by root division. For this, you need to cut the underground rhizome-like roots into sections 1.5 to 15cm long, maintaining at least one bud and some hair-roots on each piece. Root division can be performed throughout the autumn months before frost, or in early spring. The cut pieces should be transplanted into soil, and after 3 weeks the plantlets should start growing.

Planting
The best type of soil is sandy or brown forest soil, rich in humus. The soil needs to be weeded regularly. The bed should be in an open, sunny place, and prior to planting should be treated with processed manure (3 - 5kg/sq m) or fertiliser (4 - 6kg/sq m). Adding grit, gravel, or vermiculite to the soil increases soil porosity and encourages growth; however, peat-based fertiliser should not be used. During the first month, the plants need to be carefully watered and weeded. Prick out the seedlings into individual pots when they are large enough to handle, and grow them on in the greenhouse for the first winter. Plant out in early summer of the following year.
On the right image: experimental field of Rhodiola Rosea >

Harvesting
The plants usually reach their maximum height in the third year after planting, but a minimum of 5 years must pass before the medicinal roots can be harvested.
Harvesting should take place in autumn, since at this time the plant stops its vegetative growth and the dry-matter content of the root is higher. Harvesting is a simple process of digging out the roots by hand. In the case of large-scale cultivation, mechanical assistance from a cultivator machine etc. would be required.

< On the left image: 5 year old Rhodiola Rosea roots

Processing the harvested roots
The gathered roots should be sliced into thin strips about 10cm long, and dried in a well-ventilated drier at 40 - 50°C for 4 - 7 days. Under these conditions the original white color of the roots turns light brown. The roots should not be dried in the sun, since strong light destroys the active medicinal component! The dried root is best stored in paper packets in a cool dry place, and will keep for up to 3 years.
On the right image: dry roots of Rhodiola Rosea >

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