Region: Upper Plains
This gorgeous plant is an annual in Zone 4 but it responds well to being dug up and overwintered in a dormant state inside for the winter. No water required. Just start watering it in early April and place it outside in late May. I then plant it in the garden when it is fully leafed out.
I love this plant. It makes a beautiful border especially for a bed of green plants. The deep purple verigated, triangular leaves set off by pale purple flowers really accent a bed. These make small mounds and come back every year. I live east of Dallas and these have worked very well here. I saw them first in the San Antonio area, so I know they work well there also.
Region: Mountain West
I adore the purple shamrock! They're great in the house or outside. Amazingly hardy, even in full sun. Yes, they get scorched in super-hot sun, but they have not frozen outside for me, and come back bigger and better. I have moved them with me, in a baggie when necessary, to & from about 6 different homes, from central CA to Oregon to AZ and to Utah, and they keep surviving and thriving.
I bought this plant as a houseplant. It is very interesting. The leaves close up at night and the flowers are very delicate and pretty. I love the purple leaves.
Most Oxalis species are invasive; however, there are some useful, sterile Oxalis options available. I use Oxalis magellanica 'Nelson' as a fine-leaved groundcover below small, non-invasive treasured shade plants, although it is not large enough to make its own statement. It carries tiny, rounded, sterile white flowers above the carpet of leaves in summer.
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