Repeat after me:
Prevention. Prevention. Prevention.
When it comes to spider mites, a little prevention goes a long way. It's tempting to treat your plants only when you see the little suckers. But by that time your plants are well and truly infested, you just can't see it yet.
What are spider mites & what do they look like?
Spider mites are tiny - around 1mm in size. They have four pairs of legs and can appear translucent. To the naked eye they look like coloured dots on your plant. Spider mites can be brown, yellow, red, green or black. The most commonly known are the red spider mites and the two-spotted spider mite.
Spider mites thrive in hot (above 30°C) and dry climates. When conditions are favourable some species can complete a reproductive life cycle in as little as 8-12 days.
Annoyingly, spider mites can also survive in humid temps below 30°C albeit with a longer lifespan and slower reproductive rate.
What do spider mites do to my plants?
Spider mites feed by piercing the plant cells with tiny 'teeth' and sucking out the contents. When the plant cells die, they turn pale yellow or white as will be evident by spotted discolouration on the leaf. That doesn't sound too bad, right? Plants have plenty of leaves...
The problem lies in the spider mites quick reproduction rate. Left untreated, a growing spider mite colony will spread from the preferred safety of the lower canopy to feed on other areas of the plant.
Do spider mites lay eggs?
A female spider mite can live up to 4 weeks, laying up to 20 eggs per day once sexually mature (they are sexually mature from 3-5 days old!)
Spider mites lay their eggs on the underside of leaves. The transparent eggs are minuscule and very hard to see without magnification. One indication of egg deposits might be a visible cluster of fine webbing used to suspend and protect the eggs.
How do spider mites get to my indoor plants?
Spider mites travel from location to location by attaching themselves to clothes, shoes, bags and even pets before catching a ride home to your indoor plants.
Side note: These critters are so small and light they can travel from garden to garden by 'sailing' on moderate winds.
How do I prevent a spider mite infestation?
Spray your plants weekly with a quality mite control product. The A-Grade team use Mr 24/7 throughout the vegetation/growth phase. It serves as a effective barrier product and disrupts the reproductive cycle of the spider mites. Use a good-quality spray bottle to effectively disperse the solution, and be sure to spray under leaves.
Practice good plant hygiene. Avoid wearing your 'outdoor' clothes when tending to your indoor grow room.
How do I treat a spider mite infestation?
Sometimes precautions aren't enough, and you will have to deal with a spider mite infestation.
There are many insecticides available to kill spider mites. As always, it's best to use a product that is as natural as possible.
An A-Grade favourite is Mr 24/7 for direct treatment of adult spider mites, add in 2 drops of dishwashing liquid/surfactant. (kills the spider mite eggs, too.) Spray every 3-4 days until flowers start forming.
To successfully prevent or manage a spider mite infestation, follow these commandments of foliar spraying:
- Thou shall not spray in direct sun/lights on.
- Thou shall spray under leaves and in between branches.
- Thou shall turn off ventilation for 30-60 minutes to allow permeation.
- Thou shall not spray when edible flowers and fruits have begun to form.
Spring is here! Good luck!