Summer and Pest Problems

How to Deal with Pests During the Summer

The main thing to remember when thinking about pest management is prevention! Prevention is always better than cure because you're tackling the issue before it ever becomes problematic.

It is impossible to prevent pests from entering the grow space, as they can be carried in unwittingly in a multitude of different ways: via your intake fan, on shoes and clothing, or even in bags of grow media. What you can do is take steps to ensure that colonies do not take hold by creating an inhospitable environment.

A weekly dose of CannaCure or SB Plant Invigorator can be all it takes to put the problem to bed.

Spider Mites

Spider mites feed by puncturing the surface of a leaf and sucking out the juice. They thrive in warm, dry (summer) conditions. Although there are many types of spider mite, the most common is the two-spotted spider mite shown above.

Spider mites live and lay their eggs on the underside of leaves. The punctures they cause by feeding appear as white dots on the top of the leaves. The other sign that your plant could have spider mites is the webbing they create. The webbing disrupts air flow around the plant, causes water loss and creates a home for fungal infections.

Infestations usually begin on lower leaves and they work their way up the plant. Confirmation of a spider mite infestation is usually acheived by holding a piece of paper under leaves and shaking them to get the mites to fall off. Black dots will appear on the paper, and you can then use a loupe or microscope to confirm that they are spider mites.

In their ideal environment, spider mites can reproduce at an alarming rate. A female can produce between 50-100 eggs in her lifetime about (3 weeks). This is how a few spider mites can turn into a complete infestation in a few days. It takes about 3-7 days for eggs to hatch and about another 3-5 days for them to be old enough to start laying eggs of their own.

Not all pesticides will kill spider mites. If you use one that's ineffective, it can actually make the situation worse because you run the risk of killing off their natural predators. If you're in the middle of an infestation, we usually recommend SMC Spider Mite Control, which is an all-natural product.

It is wise to reapply the pesticide 3-4 times with about three days in-between. This helps to break the cycle, killing the spider mites as they emerge from the eggs, before they can reach adulthood and start laying eggs of their own.


Aphids include greenfly and blackfly but they come in a variety of colours.

Like spider mites, aphids feed by puncturing the leaf and sucking out the sap.


Whitefly are not aphids but they are very similar, and they breed like crazy! They feed the in the same way as spider mites and aphids, and the damage they cause is similar. They produce a sticky substance called honeydew which can attract fungal infections.


Like the other pests mentioned in this blog, thrips are tiny insects that feed by puncturing plant leaves and then sucking out the juice. They have wings and can fly, making it very easy for them to spread.

They are only about 1mm long and very slender, appearing as tiny slivers. Like most of these pests, you will probably need magnification to identify them. Their incessant chomping is like 'death by a thousand cuts', gradually slowing down growth, increasing stress and reducing yields.

The leaf damage they cause often looks like silvery streaks, leading to brown patches as whole areas of each leaf starts to die off.

Unfortunately, the problems they can cause does not end there. Thrips, along with aphids can carry plant viruses which they transmit to plants when they bite into plant tissue, most notably the tobacco mosaic virus which, as its name suggests, causes a mottled "mosaic" pattern on plant leaves.

Thrips become active during early spring. Eggs, which are embedded in plant tissue, hatch out and the nymphs become adults about a couple of weeks later. Adult thrips live for around a month.

As we mentioned earlier, take preventative measures to ensure that thrips never become an issue. If you've left it too late, take a look at Spray2Gro, which is great for treating thrip issues.

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