Oxalis Tetraphylla IRON CROSS Shamrock/Wood Sorrel (Bulb/Not Plant) - US Seller! Tetraphylla IRON CROSS mixes easily into pots and flower beds providing deep purple and green tones and accents of pink when flowers are in bloom. EXTREMELY EASY TO GROW!! This is a great plant for even the most inexperienced gardener! It needs little watering once it is established. The only thing you must remember is that this is a shade/semi-shade plant. It does NOT like FULL sun! It likes some sun - like under a tree or a shaded patio - just not full sun. * These will go through a period of dormancy which will vary depending upon the area where you live. This typically happens in the warmer months. When these go dormant, just continue to water once a week or so that the bulbs do not dry out and they should sprout again when the time is right. Instructions for planting: Plant the bulbs 1 inch deep and 1 inch apart in well draining soil. They can be planted closer together if necessary. Water every other day until established, and then, water as is normal for your areas. Outdoors they like a shade or semi-shade, and indoors they like a bright sunny window.