There are many varieties of Thrips, being the Frankliniella Occidentalis – also known as western flower thrips – the most commonly found in cannabis plants.
The western flowers thrip is originary from California and was introduced in La Península (Almería) in 1986 from Holland, causing considerable damage to cotton crops. Today, it is one of the most common pests worlwide, since it can damage a large number of plant species.
Potassium soap helps to prevent and erradicate thrips
Cannabis leaf with symptoms of thrip infestation
As usual, we recommend you to have your growing space and its surroundings clean and free from dead plant material, etc. Using blue adhesive strips for thrips allows us to kill most adults, being also usefull to check if we actually have thrips in our crop, since they’ll get “glued” to these strips.
Thrips are one of the most common pests in cannabis crops, especially in indoor growing spaces and greenhouses. These are one of the smallest winged insects, measuring 1.2mm (females) and 0.9mm (males) when adults. Eggs measure around 200 microns and are withish in colour, being layed in the plant tissues. Normally, thrips are found on the underside of the leaves.
Using potassium soap or natural pyrethrins regularly will help us to prevent the appearance of thrips, also to erradicate them if we don’t want to use chemicals. Expelex works great for this pupose.
While not being extremely agressive with plants, thrip pests are common in indoor growing tents or rooms. As happens with red spider mites, thrips need high temperatures to appear and can be persistent if not treated properly. The first signs are small silver dots/stains on the surface of the leaves, which are the places were thrips have bit or layed their eggs.
Thrips attack a large number of plants (Photo: Jean and Fred)
Thrips are a very common pest in cannabis plants, especially in indoor growing spaces or greenhouses. If you want to know ore about this pest and how
Neem Oil will leave an unpleasant taste/smell on buds when used to treat flowering plants, so don’t let this stuff get near your buds! There’s also some evidence Neem oil may be harmful to humans so use with care! That being said, Neem oil is an all-natural remedy that is very effective against many different types of bugs and mold. You will need a mister (also called a “One-Hand Pressure Sprayer”) to spray all the leaves evenly since neem oil and water can separate easily.
Adult thrips are small, fast-moving insects, while young thrips look like tiny unmoving pale worms on the leaves. In fact, thrips can come in many forms, from wormy nymphs to dark or golden winged insects, depending on the stage of life and where you live.
Fatty acid salts or insecticidal soaps can be a good choice against thrips. They weaken the outer shell of thrips but are safe to use on your plants and they don’t leave much of a residue.
A thrip nymph looks tubular and worm-like, unlike an aphid nymph which looks like a tiny white bug
Pyrethrin based insecticides are not very toxic for humans and degrade quickly, which is why they’re commonly recommended for vegetable gardens. You will need a mister (also called a “One-Hand Pressure Sprayer”) to spray all the leaves evenly.
Here’s a picture of an adult thrip on a finger for scale – they’re tiny!
Recommended: Monterey Garden Insect Spray with Spinosad
Pyrethrin products break down quickly, over the course of just a day or two. The major problem with them is they are very toxic to bees. Although cannabis plants generally don’t attract a lot of bees, please use this as a last resort, and also try to use it right after the sun goes down because bees sleep at night. This lets it start to break down before they wake up.
Note: Most spinosad products are effective for only about 24 hours after being mixed with water, so only mix as much as you will need per application. Anything left over will be waste.
If you see tiny, wormy little bugs, dark winged insects or bronzed discoloration on the leaves, you may have thrips. Learn how to get rid of them!