Oxalis adenophylla is a hardy oxalis (or as hardy as they come into USDA zone 4/5) and deserves to be in every rock garden.
It produces scads of pink flowers in June-July and the flowers are held 6-8 inches above the plant.
Plant it in the full sun to part shade (the more you reduce the light, the fewer flowers it will produce).
Put the base of the bulb approximately 3 inches deep and 3-5 inches from other bulbs.
If youre unsure whether this bulb will live in your garden, you can dig it up in the fall and store it cool and dry over the winter to replant again in spring.
Oxalis does make a good container plant as well as a garden performer.
In well-drained soils, in a protected area, the bulb will naturalize and self-sow.
I note there are other non-hardy species of oxalis adenophylla.
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