Growing Periwinkle in a pot

Once established, periwinkle is remarkably low-maintenance and tolerates neglect better than most groundcovers. Watering is rarely necessary except during prolonged dry spells in summer, particularly in the first year or two. Periwinkle has moderate water needs and copes well with typical rainfall in temperate climates. If the leaves start to wilt or look dull, give the planting a thorough soak rather than frequent light sprinkles. Feed periwinkle once a year in April with a balanced general-purpose fertiliser or a light dressing of well-rotted compost or blood, fish, and bone. Scatter it evenly over the foliage and water in if rain isn't forecast. Avoid overfeeding, which can promote excessive leafy growth at the expense of flowers and make the plants more prone to disease. Periwinkle grows well in relatively poor soil, so a single spring feed is sufficient. As an evergreen hardy to zone 4a, periwinkle requires no special winter protection in our region. The foliage remains green throughout the year, providing valuable ground cover and weed suppression even in the coldest months. Top up mulch in autumn if the layer has thinned, but keep it away from the stems to allow air circulation. Periwinkle is generally pest- and disease-free, though it can occasionally suffer from rust or leaf spot in very damp, poorly ventilated conditions. Remove and bin affected leaves promptly. Slugs and snails rarely bother it. The main "problem" with periwinkle is its vigour—it can become invasive in small gardens, so site it carefully and be prepared to trim back spreading stems annually to keep it in check.