Time for a controversial opinion… While indoor gardening is often considered second fiddle to its outdoor cousin, I think it is superior in pretty much every way. First, it is far more democratic. The vast majority of people have access to a sunny windowsill, but those with substantial outdoor space (and the resources needed to landscape this) are significantly more limited. Secondly, for those living in less idyllic climes, it means you keep growing all year round, even at 10 o’clock on a stormy February evening. It even comes far less encumbered with dusty, cultural baggage of not only the “right” way to do things, but even the “right” way to think about them – including the idea that indoor horticulture is not “real” gardening.
However, there is one aspect of gardening in the great indoors which can put it at an enormous disadvantage: pest and disease control. Perhaps counterintuitively, although living rooms and conservatories provide in many ways a sealed sanctuary, protected from external threats, these very same conditions mean that if a pest hitches a ride on new plant purchases they can quickly reach plague-like proportions. In a stable, warm, indoor climate with an ample food source and no predators, populations of mealy bug, scale insect, red spider mite and thrips can explode, and quickly cripple the health of many plants. This has been made especially likely in recent years as most of the big houseplant growers in the Netherlands, who supply the vast majority of the market, have done a really commendable job improving their environmental footprint by slashing the amount of pesticides they use to essentially zero. When once plants arrived pretty much sterile to store, they now often come with a hitch hiker or two. Sometimes doing the right thing can have its downsides!
Fortunately, there is an incredibly simple practice that can dramatically reduce the risk of an outbreak striking your indoor oasis – and that is proper quarantine. This is standard practice at all the big botanic gardens and commercial growers, and on a domestic scale takes no more than five minutes work. The first step is to carefully inspect any new plants for signs of pests and disease. You don’t have to be an expert to do this, as most have quite easily identifiable tell-tale signs. If new growth is contorted, mottled or yellow, or there is any evidence of tiny bugs or sticky residue on leaves or stems, this is not a good sign. The best time to do this, of course, is before the plants enter your door. So give everything a good once over at the nursery or garden centre before you make your purchase. If in doubt, do not buy them. If you’ve bought online or via mail order, take pictures and contact the supplier straight away.
Once in your home, place new arrivals in a separate room from the majority of your collection. For tiny flat dwellers like me, this can be tricky, but even a 6ft distance can make a difference. I like to give them a good spritz with a commercial “plant invigorator”, which contains low doses of safe, mild detergents, which act to physically tackle any potential mini beasts that have missed your checks. Keep the plants there for two weeks, if they have stayed symptom free then they can be set free to mix with the rest of your collection.
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