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Check out our comprehensive A-Z of RHS advice
We offer expert advice on a wide range of garden features; see our A - Z directory.
Saintpaulias, commonly known as African violets are widely grown, attractive houseplants originating from tropical East Africa. They are available in a many colours from white, through pink and red to purple and various flower types. With careful cultivation they can flower for many months and the compact plants are ideal for small spaces such as windowsills.
Lawns in damp or poorly drained conditions can suffer from unsightly problems such as cyanobacteria (an algae-like growth), dog lichen and liverworts. Cyanobacteria in particular can make the lawn very slippery.
Algae, lichens, liverworts and moss are often found growing in damp or shady places in the garden on plants, soil and hard surfaces. They do not cause any harm, and can usually be tolerated as they can give a mature look to a garden. But they can make paths and lawns slippery and make ponds and borders unsightly so control is sometimes necessary.
It is common to find growths such as algae, lichens, liverworts and moss growing on hard surfaces. Contrary to popular belief, they do not damage what they are growing on, but can cause patios, drives, paths and steps to become slippery.
Green growths such as algae, liverworts and moss can accumulate on the glazing and surfaces of greenhouses, where they are unsightly and cut out light. They can be controlled by improving hygiene and ventilation.
Aquatic plants enliven a pond and help create a wildlife habitat. They are not difficult to plant, although there are a few key differences from planting on land.
Aquatic weeds (or pond weeds) can normally be tolerated in small numbers, but it is when they make excessive growth that they become a nuisance, particularly in summer. In garden ponds control is relatively easy, but in larger ponds and lakes it is more difficult.
In the UK avocadoes are grown as houseplants for foliage interest until becoming too large. In places where frost is rare they are occasionally seen growing outside as trees. For most, though, growing an avocado indoors from the stone is a better bet and fun for adults and children alike.
The many cultivars of Rhododendron simsii (often called Rhododendron indicum) are popular pot plants which are brought on, or ‘forced’, in warm, humid conditions for sale at Christmas.
Bananas (Musa and Ensete spp.) produce large, elegant leaves and the occasional bunch of fruits, which certainly make a majestic addition to any garden or conservatory. Although they are tender plants, some species are hardy enough to leave outside over winter, especially in the milder parts of the UK, so they are worth experimenting with in the garden.
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