In this article, I will share 15 Basic Greenhouse Pest Control Tips and Tricks which will help you to save your greenhouse plants from harmful pests and insects. So let’s get Started!
The first thing you need to decide when you set up your greenhouse, regardless of any system you have outside is whether you are going to utilize a traditional system or an organic system?
Personally, I have an organic garden, so it is simple for me to extend that ethos to the greenhouse. I do however appreciate the value of the standard system that utilizes chemical fertilizers and pest control. However, because the greenhouse is a separate, confined eco-system it is definitely worth considering an organic or semi-natural environment for the greenhouse.
Because the greenhouse is an enclosed environment, generally natural pest control such as birds and certain insects are not present, so if you do get an attack of pests you need to act quickly because the sheltered, warm, humid conditions together with abundance of things to eat in the greenhouse give an excellent home and breeding ground for pests. If they manage to find their way into your greenhouse, they have found their perfect larder and it really can feel like being under attack for the person dealing with the problem.
Some of the most common greenhouse pests to look out for are aphids, caterpillars, fungus gnats/sciarid flies, leaf miners, mealy bugs, mites, slugs and snails, thrips and whiteflies. A few can be picked off and destroyed, but look carefully and act quickly where there are a few there could soon be a legion.
In all Cases:
- Check all plants for health and bugs before putting them in the greenhouse.
- Know your plants, if one or some don’t look right, investigate why? Get to know what is normal and act quickly.
- Keep the greenhouse clean and tidy, because a well-ordered greenhouse is easier to manage.
- Thoroughly clean the greenhouse and equipment between different growing seasons.
- It is worth a little effort to keep your plants healthy. Healthy plants bounce back better from an attack.
These 5 points given above are the Basic Greenhouse Pest Control Tips and Tricks which are applicable to both conventional greenhouses and organic greenhouses. Next, we will focus on Pest control techniques for an organic greenhouse and in the end, we will provide chemical greenhouse pest control tips and tricks.
Organic Greenhouse Pest Control Tips and Tricks:
When growing using organic systems prevention is better than cure, the organic gardener strives for harmony. The aim is to make the greenhouse the perfect growing environment for the plants inside. The organic gardener will utilize nature in the greenhouse to optimize ideal growing conditions for healthy plants.
The simplest form of pest management for the greenhouse is the same as for the organic garden and that is companion planting. There are many plants that repel insects and other pests. So, if you have something that you want to grow and know that it attracts certain pests, a simple solution is to grow a plant alongside it that repels the particular pest. Grow Lemongrass to deter fruit flies or Lavender to deter greenflies are two examples.
Concentrated Plant Extracts:
Some essential oils contain for example limonene, citronellal or pulegone that are often incorporated in commercially available repellents and even personal repellent products as well. Utilised in the greenhouse either diluted and via a spray or putting onto cloth that is hung in the doorway or window is frequently a good method in the fight of repelling flying insects. Lemon, Lavender and Eucalyptus are all very good.
Neem Oil is from the Neem tree and quick action is needed to spray the insect(s) as soon as they are seen in the greenhouse. The oil works by suffocating the insect. Neem does also work as an insect deterrent. Insects do not lay their eggs where the oil has been sprayed. So a repellent spray to plants near doors and openings may be all that is required.
Nematodes are especially bred predators targeted at specific pests in the garden and greenhouse and can be ordered for fast delivery when a problem is discovered. The nematodes are stirred into a watering can of water and watered into the soil where they will destroy the insects or slugs there. It is important to note that Nematodes are pest specific; it will not work to hope that the Nematodes for one pest will eradicate another as that is not the case. This method is most effective for treating infestations of chafer grubs, slugs, leatherjackets, vine weevil or sawfly. It does not work as a preventative, the Nematodes need the pest to live and once they have eradicated the problem they will die.
Sticky paper rolls or window stickers work by attracting the insects and then capturing them on the glue. These can be strips or cards that are hung up or labels that stick to the glass. It is also possible to buy larger card versions which work well around the plants in a larger greenhouse.
An advantage of these is that as well as fighting against pests they are also a useful way of monitoring the numbers and types of insects in the greenhouse. Remember to replace if they become full or dry out.
Predator Insects such as Ladybugs or Lacewing:
Both these insects are carnivorous and live on other insects, they will not harm the plants and if introduced where there is a problem they will work quickly to eradicate the problem insects for you.
Consider a Moat:
Ants are a nuisance they undermine plants and disrupt the root system and this can have a devastating effect on the plants. A useful way to keep ants out of the greenhouse is to create a moat around it, ants don’t like water and will not cross the moat if using this system remember though that they can use any steps made for our use or plants that brush up against the greenhouse to gain entry. This system though does need careful thought, you do not want to create standing water that will attract midges and mosquitoes that you do not want in your garden or near your greenhouse, so consider a way to have movement in the water, such as a solar pump. Tea Tree Oil and Peppermint are also good to deter and eradicate ants.
Fitting screens to any openings will deter flying insects. These are usually made of fine metal, plastic or fabric mesh, but they will reduce the air flow and prevent pollinators from entering as well. An added deterrent is to wipe over metal mesh daily with a bug busting essential oil.
Organic Slug and Snail Pellets/Eggshells:
Slugs and snails are often a problem if they find their way into the greenhouse. As well as Nematodes there are some organic pellets available, take care that you are buying organic pellets and that they will not affect other life forms. Putting a ring of crushed eggshell around tender young plants works very well as a top barrier, but sometimes slugs will burrow underneath to reach the plants.
Commercially produced natural insecticides such as Azadirachtin from Neem and Pyrethrin from Chrysanthemum can be effective when used regularly, just make sure you have chosen organic products for your organic garden.
Following the above, Greenhouse Pest Control Tips and Tricks will greatly eradicate the presence of the insects and pests from your greenhouse and will ensure the health and growth of your plants.
Most successful gardeners will use a variety of methods to control pests. The simplest rules to remember:
- every action has a reaction
- prevention is better than cure
- If a pest is more than a single, act swiftly.
If you put up mesh to keep out those pest insects, you will also keep out the pollinators. Therefore, you will need to manually pollinate any plants that require pollination.
If ants are a problem where you live, building a moat will keep them out of the greenhouse, but standing water attracts other unwanted pests such as mosquitoes. Only consider a moat if the ant problem is severe and you have a way to keep the water moving.
Companion planting, concentrated plant extracts and Neem spray to help prevent or lessen an outbreak of pests is better than going to battle if you get a full-on attack, having done nothing to prevent it.
A single pest can be easily squashed and eradicated that way, look carefully for more, pick off and kill those you see. Return after an hour. Are there any more, return the next day, are there any more? If yes, act swiftly to tackle the problem.
Increasingly people are becoming concerned about the overuse of chemical pesticides, rightly so because they are non-biodegradable and often highly toxic and that is why many of us choose to grow our own food in the first place. This is good for the organic and natural gardener because it means that the environmental bio-pesticides are becoming more easily available and as sales increase they are coming down in price due to the demand and higher level of manufacture.
Lots of people still like to use chemicals and because chemical pesticides are designed to kill insects, remember many of them will often kill the good insects that you want, the pollinators and insect predators as well as the plant eaters or spoilers that you don’t want. Consider as well that they may kill fish if they get into waterways. Always read the label and check what you are buying.
Chemical Greenhouse Pest Control Tips and Tricks:
If you want to go the pesticide and fertilizer route, that’s fine, that is up to you. Here are some more tips that will help you overcome pest attacks in the greenhouse.
Dish Washing Up Liquid:
A tried and tested method that does help eradicate greenfly and black fly is to use a spray made with washing up liquid diluted with water. You may wonder why this is in this section? Well, unless you use organic washing up liquid, most washing up liquids contain ingredients that are not strictly compatible with organic systems. So, if you have an organic greenhouse you may not wish to use this method. However, there is also a reason why it is first in this section. If you get an attack of greenfly or blackfly and having nothing else for your organic greenhouse. I’d say it’s acceptable to use this sparingly as a fast defence whilst setting up another system.
Dress for the Occasion:
Insecticides can be quite toxic and it is advisable to wear protective clothing, use in a ventilated area and avoid the eyes. Remove and wash clothing worn whilst using the chemical and wash hands thoroughly. Always read the label carefully and follow the instructions.
There are many insecticide products on the market to choose from. If using on a crop you intend to eat, take care to ensure that the product is recommended for use on edible crops. Azaguear, Botanigard ES and Botanigard 22WP are examples of products that are recommended to use on most edible plants and treat for most insects. However, always ensure the products you use are suitable for the pest you are trying to eradicate and its life stage.
Chemical Slug Pellets should be used sparingly, too many will just attract slugs and snails into the greenhouse; the trick is to just use enough to deal with any problem you already have. Also, it’s advisable to select the pellets that are not harmful to pets and wildlife that you may want to attract to the garden because the slugs may go outside to die and could cause secondary poisoning to anything that eats them.
The greenhouse is a warm, sheltered environment and may on occasions attract rodents such as rats and mice. These are serious pests that carry diseases and an effective way of eradicating them is to use rodenticide poisons that will attract and kill them. Again, it is worth seeking out a version that will not be harmful to pets or wildlife that may eat the carcass.
Remember, prevention is better than cure, a well-managed greenhouse using companion planting and a few simple prevention systems such as mesh over openings combined with Neem will pay in the long run.
But if you do find yourself worried by whitefly or annoyed by aphids, prepare for battle and quickly adopt these useful tips.
The greenhouse should be a place of harmony and tranquillity, not a battleground.