Hidcote hypericum, more commonly known as St. John's wort, is a perennial herb with bushy foliage and creamy yellow flowers. It grows from 2 to 4 feet tall and up to 4 feet in diameter. Hidcote hypericum works well as a border plant, but can also be used as ground cover if planted closely together. It requires very little attention once established. This plant does best in full sun to partial shade and is hardy in USDA Zones 5 through 9.
Dig a hole that is the same depth and 1 foot wider than the root ball of hidcote hypericum. Use a knife to make several 1-inch deep vertical cuts around the root ball. Loosen the roots with your fingers to encourage them to spread out after planting.
Place the root ball into the planting hole, and fill halfway with peat moss. Finish filling the hole with the loosened soil, and tamp down firmly to remove air pockets. Water until the soil is very moist to the touch.
Continue to water anytime the top 1-1/2 inches of soil feels dry.
Fertilize once each week with water-soluble fertilizer mixed at half the recommended strength.
Prune the plant back all the way to the ground in late winter or early spring, before new growth begins.