Campanula isophylla | Italian Bellflower Care Guide

About Your Campanula isophylla

Congratulations — you are now the proud owner of a Campanula isophylla, commonly known as the Italian Bellflower or Star of Bethlehem. This cheerful, trailing plant is beloved for its abundance of delicate star-shaped flowers in soft lilac, blue, or white, which cascade beautifully from hanging baskets, shelves, or windowsills. Native to the rocky slopes of northern Italy, it is surprisingly easy to care for and, with a little attention, will reward you with weeks of continuous blooms.

When Your Plant First Arrives

Your Campanula has been carefully packaged for its journey, but give it a little time to settle before making any changes. Follow these simple first steps:

• Unpack gently — remove all packaging and check the plant over. A little wilting after transit is perfectly normal and nothing to worry about.
• Find a bright spot — place it in a position with bright, indirect light. A north- or east-facing windowsill works well. It can tolerate some gentle morning sun, but avoid harsh afternoon sun which can scorch the delicate flowers and foliage.
• Check the soil — give the compost a gentle feel. If it is dry, water it lightly to settle the plant into its new environment.
• Let it settle — avoid repotting or moving it for the first couple of weeks. Give it time to adjust to its new home.

Watering

Campanula isophylla likes to be kept consistently moist but not waterlogged — it dislikes both drought and soggy roots. In spring and summer, water regularly, checking the top centimetre of compost and watering when it feels dry to the touch. In autumn and winter, reduce watering significantly as the plant enters a period of rest.

When you water, do so thoroughly and allow any excess to drain freely — never let the pot sit in standing water, as this can lead to root rot. Avoid getting water on the flowers where possible, as this can cause them to brown prematurely.

Light

Campanula thrives in bright, indirect light. A north- or east-facing windowsill is ideal — enough light to encourage prolific flowering without the risk of scorching in direct summer sun. If your plant becomes leggy or produces few flowers, it is likely it needs a little more light. If the leaves appear bleached or the flowers fade quickly, move it slightly further from the window or into dappled shade.

Temperature & Humidity

Your Campanula prefers cool to moderate temperatures and is happiest between 10–20°C. It is not frost hardy, so keep it indoors during the colder months. Importantly, it actually benefits from a cool winter rest — keeping it somewhere cooler (around 10–12°C) from late autumn through to early spring helps it to flower more abundantly the following season. Avoid placing it near radiators or in very warm, stuffy rooms.

Average household humidity is perfectly adequate — no additional misting is required.

Growing Outdoors

Campanula isophylla can also be grown outside in the garden during the warmer months. It makes a beautiful addition to containers, hanging baskets, rockeries, or the front of a sunny border, where its trailing stems and starry flowers can spill freely. Place it in a sheltered spot with bright, indirect or dappled light — a little gentle morning sun is welcome, but protect it from harsh afternoon sun and strong winds.

Move it outside after the last frosts, typically from late May in the UK, and bring it back indoors before the first frosts of autumn. Campanula isophylla is not hardy enough to survive a UK winter outdoors, so it should always be overwintered inside in a cool but frost-free spot. When grown outside, check soil moisture more frequently as containers dry out more quickly in warm weather.

Feeding

Feed your Campanula with a high-potassium liquid fertiliser (such as a tomato feed) every two weeks during spring and summer to encourage continuous flowering. There is no need to feed during autumn and winter when the plant is resting. Always water before feeding to avoid applying fertiliser to dry roots.

Deadheading & Pruning

Regular deadheading — removing spent flowers — is the single most effective thing you can do to keep your Campanula blooming. Pinch off faded flowers as soon as they finish to encourage the plant to produce new buds rather than setting seed. At the end of the flowering season, cut the plant back by approximately half. This hard prune encourages fresh, vigorous growth in spring and a fuller, more floriferous plant the following year.

Repotting

Campanula isophylla is a relatively compact plant and does not need repotting frequently. If the roots are visibly escaping the drainage holes or the plant dries out very quickly after watering, it is ready for a slightly larger pot. Spring, as new growth begins, is the best time to repot. Use a good-quality peat-free multipurpose compost with added perlite for drainage.

Need More Help?

If you have any questions about caring for your Campanula isophylla, we’re always happy to help — just get in touch at info@rootedbycatherinegray.co.uk