Spider Mites or Thrips – Which is worst

close up on spider mites and thrips on marijuana

Hey guys, with our current situation (infestation of some type) we decided to do a quick post comparing what is worst, thrips or spider mites?

If you’ve been following up on our grow journal you’re aware that we’ve been battling an infestation; At first we thought it was spider mites but now we’re positive it’s Thrips (How to tell the difference? Here’s our guide).
The signs of both these little suckers are actually extremely similar, showing small white marks on your leaves, some more impacted than others. Luckily the actions to get rid of both are pretty much the same, but we’ve covered all that in our guide linked above.

So to recap:

Comparison between Spider Mites and Thrips

Spider mitesThrips
Easy to killNo – Depending on the type they can develop resistances, making them so hard to killYes – A repeated treatment will do the trick
ImmunityYes – Very strong capability to develop resistance to any treatment.
To know more about spider mites check out our in depth guide
No – Thrips are not known to immunize themselves.
Visible by the
naked eye
Barely – Since they live under the leaves and measure
between 0.5 mm and 1 mm they are very hard to see
A little easier – You can spot them moving around above
the leaf or flying around. They get up to 1.5 mm and white or
black depending on the stage of life making them easier to see.
Resistance to
Strong – Spider mites are know to be very resistant
to most organic or chemical treatments.
On top of that as we said further up they will develop an
immunity very quickly.
Low – Thrips will die on the first time you spray them. This issue
lies with the eggs, that’s why it is important to respray every 3 day
at least 3 times.
Threat level
to marijuana
Very High – Spider mites are one (if not the) of the most
feared Marijuana Pests and for good reason.
They eat away the chlorophyll of the leaves
Medium/High – The direct danger to the plant is actually about the same
since Thrips attack and finish by killing you leaves. Furthermore once
they’ve developed enough they actually fly around from plant to plant.What really reduces their danger is the fact that you can treat the
infestation fairly easily. Remember to spray every 3 day at least 3 time
after the first application.
Speed of
High – In optimal conditions and without and treatment
in a month there can be over 800 000 individuals!
Prevention and Early Action is key.
Medium/High – Once thrips have matured and are able to fly they will invade you grow space quickly.

Once they’ve hatched in the soil they will develop themselves on that plant. Once they’re
able to they will fly to the next plant, feed on it and then lay eggs in that soil.

We’re currently working on a full guide on thrips, once we’re done with it we’ll link to it so don’t hesitate to come back 😉

In the mean time check out our guide on Spider Mites, the grow journal or all our other tips!

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