Most people who enjoy houseplants will admit to accidentally killing quite a few! Here’s how to care for some winter favourites.
• Poinsettias (Euphorbia pulcherrima) hate draughts and like brightness but not full sun. When the show is over, prune them back quite hard and repot them during early spring.
• Amaryllis bulbs need a brightly lit position. Water sparingly until the foliage develops, then gradually increase watering, taking care not to drown the bulb. After flowering, reduce watering and allow the plant to die down. Store the dry bulb ready for next year.
• Prepared hyacinth bulbs that have finished flowering can be hardened off by gradually acclimatising them to the outdoor air. Plant them outdoors when the soil is frostfree and they should flower every spring.
• Cyclamen need bright light but keep them away from radiators. Remove their spent flowers by pulling the whole stalk, not just deadheading. Reduce watering as the foliage turns yellow, then allow the plant to become dormant for the summer. You can plant them in a shady spot in the garden or give them some new compost and start watering regularly once new growth appears.
• The vibrant winter flowers of indoor azaleas will last longest when kept out of direct sunlight and away from a heat source. These plants are ericaceous, so they prefer rainwater or deionised water to thrive. After flowering, keep them outdoors in a shady, damp spot for the summer and bring them back indoors before the first frosts.
Gardening Myths
Gardening myths or magic? Gardening tips have been handed down for generations, but times move on, and opinions, fashions and practices can change. How do you know which guidance is wise?
1: Washing-up liquid is a great way to kill aphids
Spraying plant pests with a weak solution of washing-up liquid does tend to work. It’s a good idea to spray the plants with clean water shortly afterwards to minimise the risk of harm to wildlife. Does it harm plants? Detergents containing surfactants do present a real risk of harm to plants, known as phytotoxicity. Some plants are more sensitive than others, particularly sweet peas, cherries, plums, hawthorns and tomatoes. It can remove the protective natural oils and waxy surface from the leaves. Soaps are kinder because they are made from fats and oils.
2: The application of fertiliser kills bacteria in the soil
Organic gardening in tune with nature is undoubtedly best, if at all possible. However, is it true that artificial fertiliser damages soil microbes? It appears not. Bacteria absorb nutrients in fertiliser, and this helps them to multiply. The only exception seems to be when synthetic fertilisers are applied in very large amounts, which creates toxins. The most significant difference between synthetic and organic fertilisers is the time they take to release their nutrients. Chemical fertiliser releases nutrients as soon as it dissolves in water, whereas organic matter releases them very slowly.
3: Digging is good for the soil
Digging and double-digging is something that many of our ancestors would have done. It’s a great way to get rid of weeds, incorporate organic matter into the soil, increase air pockets and help with drainage in compacted areas. Right? Maybe not if we take the advice of today’s gardening experts and soil scientists. Not only is digging hard work, but it is generally thought to do more harm than good. It can quickly destroy the network of earthworm tunnels that provide air to roots, sever beneficial threads of fungus that work in harmony with plants, and disrupt the ecosystem beneath the surface. It can also stimulate microbes that release greenhouse gases into the air. Instead, apply organic mulch to the surface, which will deter weeds and allow earthworms to take it into the soil. Dig when you need to plant something new.
by Caroline Knight
