By William Mills
Pests and Disease.
In the photograph of the Hibiscus the round holes in its leaves are caused by snails eating them.
When outside plants should be surrounded by a liberal helping of slug pellets which are available from most hardware shops and garden centres. If any leaf damage is seen, we need to check each one carefully to find and dispose of the culprit.
One suggested method to keep plants healthy over winter is to wash their leaves with a deluge of water. To prevent soil from being washed out of the pot use kitchen aluminium foil to completely enclose the base, then it’s safe to place the plant in the bath and shower with tepid water.
The Thornapple in the next photo has fungus disfiguring its leaf. Any affected need to be snipped off and the plant sprayed several times a few days apart with a propriety anti fungus spray. Although a small snail can be seen near the spiky seed pod there is no sign of the tell tale holes because this type of plant has its own defensive system. The plant contains both a powerful narcotic and poison within its leaves. A pest eats just enough leaf to get a taste of the narcotic then falls off dead as a result of the poison also ingested.
The third photograph is of a Jasmine, its pot encased in bubble wrap. As its shoots are entwined in a trellis it’s not possible to bring indoors. Frost kills a plant by harming its roots, so these must be protected if it is being left outside over winter.
Plants brought indoors need their moisture level carefully monitoring which can be done with an inexpensive probe. If the roots are allowed to stay waterlogged they will rot causing the plant to die. Don’t water the base unless it’s really dry and the plant’s weight feels lighter, but do regularly mist them, once or twice daily is ideal. Leaves do fall during the winter period and hopefully new ones will grow next spring.
As winter descends and daylight gets weaker we will consider the merits of artificial light in the next edition.