Oxalis (Shamrocks) Planting & Growing Guide

Where to Plant

As they're easy growers both in-ground and in containers, feel free to use this plentiful plant for edging, container gardens, or as indoor windowsill accents. Oxalis love sunlight but appreciate some protection during the hottest part of the day. For example, south-facing windows are perfect for winter but may be too hot during the summer. In USDA zones 6 through 10, it can grow outdoors in borders or edgings but should be treated as a houseplant in cold winter areas.

When to Plant

Oxalis go dormant in the summer rather than the winter and prefer being planted in the spring, as this lines up with their regular blooming period. Many species flower sometime between spring and summer with possible repeat blooms in the fall. While foliage typically emerges 3–4 weeks after planting, flowers can take 8–10 weeks to arrive.

How to Plant

• For outdoor landscape planting, locate an area with well-drained soil where your Oxalis will receive plenty of sunlight. If you live in a warmer climate, be sure to provide some afternoon shade. Dig holes large enough to house your Oxalis bulbs and position them approximately 3–4 inches apart and at a depth of 1–1 ½ inches. After placing the bulbs in the holes, cover with the surrounding soil and gently tamp down.
• For container planting, find an area in your home with bright direct light and fill your container about three-quarters full with a well-drained potting mix. Water to settle the soil before placing the bulbs on top, spacing them several inches apart. Cover the bulbs with 1–2 inches of additional soil. If your Oxalis arrived pre-planted, feel free to skip this step and use the shipped container.
• Water lightly, ½ to 1 cup will usually do the trick until top growth emerges.

How to Grow

• Water lightly during active growth about once per week when the top half of the soil feels dry.
• Fertilize your Oxalis lightly with a diluted liquid fertilizer once every month while the plant is actively growing.
• Prune away dead foliage in late summer as the plant begins to die and slip into dormancy.
• Stop watering and fertilizing while your plant rests in its dormancy period.
• Resume watering and fertilizing once your Oxalis begins to regrow in the spring.

Oxalis Tips & Tricks

• Expect the brilliant foliage to appear within 3–4 weeks of watering and delicate flowers in about 10 weeks.
• Watch in awe as the foliage and flowers open and close in response to the surrounding light.
• Plant your Oxalis bulbs in groups for a spectacular display.
• Treat Oxalis as a houseplant in colder winter areas. In USDA zones 6 through 10, it can grow outdoors in borders or edgings.
• Transplant your Oxalis by digging a hole deep enough that you can set the plant with its crown slightly above the soil line. Spread the roots evenly over the hole and tap gently to remove air pockets as you replace the soil. Water thoroughly to complete the process.