Hypericum St John’s Wort – Pruning, Winter Care and Fertilizing. Prune these shrubs in early spring before they leaf out. Remove 50% to 75% of the top of the shrub maintaining a mounded form. Remove the heaviest canes all the way to the ground. When pruning your St. John's wort, use a clean, sharp pruning shear and selectively remove some of the branches. Also, remove any dead or crossed branches. Do not use an electric hedge shear to Estimated Reading Time: 3 mins.
SavATree - Springfield. Verified Ratings. Call Now.Areas of Expertise. Artistic & maintenance pruning / Tree trimming. Custom blend fertilization / Organic tree fertilizer. Insect, mite and disease treatments. I have grown my St. John's Wort Hidcote for about 5 or 6 years in a south-facing bed of my zone 5b garden. The soil is fairly heavy clay but with good drainage and amended with compost.
It has been one of my favorite shrubs, growing to about 3ft tall with a fountaining habit Cultivar: Hidcote. Remove any dead or damaged branches, and you may want to remove some of the other branches to provide better airflow between the plants. Prune off 1/3 of the height of each bush. St. John’s wort will grow flowers only on the new growth.