How do I control greenhouse pests?
The first rule about greenhouse gardening is hygiene; it's essential to keep the greenhouse neat and tidy to remove as many hiding places for greenhouse pests. A pile of used flowerpots makes a great shelter for snails, slugs and all manner of greenhouse pests. When you've emptied a pot, either pack it away outside or clean it straightaway for reuse.
Keep on top of greenhouse housework, mop up any spillages and remove as much rubbish as you can. Pick off dead leaves, take outside any dead plants and make sure you always use clean, fresh compost for sowing, cuttings and potting up.
Avoid using rainwater in the greenhouse unless you are watering mature plants.
Ensure that your greenhouse is always well ventilated to keep the air flowing freely through your plants, avoid overcrowding and keep a close eye on your plants for signs of fungal damage and pests. Act swiftly, sometimes the removal of a leaf or two or squashing the odd bug, is all it takes to nip a problem in the bud. Once you've spotted an issue don't let it get out of hand, it's easier to stop an epidemic of bugs early on before they have moved all around the glasshouse. Keep an eye under pots and in damp corners for slugs, slug eggs and more. Watch sappy fresh growth for the first signs of aphids, they can be hard to see as they are often the same colour as the stem. Just one or two aphids can become hundreds in a few days and then the problems start. You can make good progress with some pests like aphids by removing them (squash them if you can bear it) as soon as you see them. Yellow sticky traps set around your greenhouse plants are a good idea early in the season so that you can monitor what pests are flying, but do not use them if you have biological control in your glass house.
Bio Control
These days biological control is the favoured method f pest control for many greenhouse owners both amateur and professional. It's a simply but effective system that exactly targets the pest problem in the greenhouse with the correct predator or parasite that needs that bug for its own lifecycle and kills it in the process. The basic facts are that these controls are naturally occurring in your garden, just in smaller numbers, so all you are doing is bringing in a concentration to deal with a problem, when the problem has gone the predator or parasite will die back. The secret is to identify the pest and employ the correct control. But there are rules too, you cannot use pesticides in your greenhouse while you are using biological controls because the insecticides aren't selective and will kill all the bugs present, even the good ones. And if you have already used powerful systemic insecticides in the greenhouse this season, these will affect any bio controls you then introduce, so you need to make a decision. There are a couple of exceptions where you can knock down a pest epidemic using a contact spray containing soft soap and then after a few days introduce bio control.
Keep on top of greenhouse housework, mop up any spillages and remove as much rubbish as you can. Pick off dead leaves, take outside any dead plants and make sure you always use clean, fresh compost for sowing, cuttings and potting up.
Avoid using rainwater in the greenhouse unless you are watering mature plants.
Ensure that your greenhouse is always well ventilated to keep the air flowing freely through your plants, avoid overcrowding and keep a close eye on your plants for signs of fungal damage and pests. Act swiftly, sometimes the removal of a leaf or two or squashing the odd bug, is all it takes to nip a problem in the bud. Once you've spotted an issue don't let it get out of hand, it's easier to stop an epidemic of bugs early on before they have moved all around the glasshouse. Keep an eye under pots and in damp corners for slugs, slug eggs and more. Watch sappy fresh growth for the first signs of aphids, they can be hard to see as they are often the same colour as the stem. Just one or two aphids can become hundreds in a few days and then the problems start. You can make good progress with some pests like aphids by removing them (squash them if you can bear it) as soon as you see them. Yellow sticky traps set around your greenhouse plants are a good idea early in the season so that you can monitor what pests are flying, but do not use them if you have biological control in your glass house.
Bio Control
These days biological control is the favoured method f pest control for many greenhouse owners both amateur and professional. It's a simply but effective system that exactly targets the pest problem in the greenhouse with the correct predator or parasite that needs that bug for its own lifecycle and kills it in the process. The basic facts are that these controls are naturally occurring in your garden, just in smaller numbers, so all you are doing is bringing in a concentration to deal with a problem, when the problem has gone the predator or parasite will die back. The secret is to identify the pest and employ the correct control. But there are rules too, you cannot use pesticides in your greenhouse while you are using biological controls because the insecticides aren't selective and will kill all the bugs present, even the good ones. And if you have already used powerful systemic insecticides in the greenhouse this season, these will affect any bio controls you then introduce, so you need to make a decision. There are a couple of exceptions where you can knock down a pest epidemic using a contact spray containing soft soap and then after a few days introduce bio control.
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