Insect free plant soil

Old Man

Old Man

Old Man

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I've been having a hard time trying to find a supplier for insect free soil for my indoor plants, of which I have
about 30 (Or had until I had a bad purchase of soil that caused a lot of problems), so I would like to ask if anybody
happens to know of a reputable supplier that one could use?

TY
 
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cocoir maybe, but blackfly can still manage to survive in the pots, they seem to really struggle to survive though.
cocoir doesnt rot or break down into organic material until 2-3 years, so you need to replace it every few years, but it's basically inert and sterile so useless to insects.
it means you need to feed your plants more often though.

if you put a small layer of sand in the bottom of your pots, and a small layer on top it probably stops most things, if you wanna go crazy instead of sand use DE ( get food grade and don't inhale the dust when you pour it..)

Diatomaceous earth (DE) is a naturally occurring, soft, siliceous sedimentary rock that crumbles into a fine white or off-white powder. It is made from the fossilized remains of diatoms, a type of hard-shelled algae. The primary component of DE is silica.


Uses:​


  1. Pest Control – DE is used as a natural insecticide because its sharp microscopic edges damage the exoskeletons of insects, causing them to dehydrate and die.
  2. Filtration – It is used in water filtration systems, pool filters, and beer and wine production.
  3. Food-Grade DE – Some types are safe for human and animal consumption and are used as anti-caking agents in food or as a dewormer in livestock.
  4. Abrasives – DE is found in toothpaste, metal polish, and other cleaning products.
  5. Gardening – It can be used to control pests in gardens and improve soil aeration.
Click to expand...



I'm guessing it could kill slugs too death by a million cuts.
 
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The soil is unlikely to have insects in it when purchased.
The problem is the insects (usually what people call fungas gnats) get in when its in the open in order to lay eggs.

The best way is as arknor says and put a thin layer of sand on the top. Type is pretty unimportant so you could pick up eg a play sand bag in the super market for a smallish quantity.

Drying the top out is another way to help keep them out (water from bottom only) but if you already have them in the plants then its much harder to get rid of them this way.
Sand will normally kill the cycle of them being in there as well.

You can also try the plastic bag method of putting the plant pot in and sealing a plastic bag around the stem. You only open up very occasionally in order to add some water.
This will generally also get rid of the bugs but it takes some time.
Most adults don't eat whats in there, its just used as a refuge and place to lay the eggs.

If your really struggling with an infestation then the only other way is to get known good soil (microwaves d a good job of sterilisation in small quantites just do it carefully)
Remove the plants from pots, wash ALL the peat/soil off and repot into known good soil.

You will have to do every pot at the same time, and you really need to be able to isolate the insects from being able to hop straight back in.
There will be some about ready to move in for sure.

Lastly, I have used this myself, spider. If you can encourage a spider into the direct area of the plant they will do it for you over time.
 
Mercenary Keyboard Warrior said:
The best way is as arknor says and put a thin layer of sand on the top. Type is pretty unimportant so you could pick up eg a play sand bag in the super market for a smallish quantity.
Click to expand...
things will still crawl int he bottom, even flies

Mercenary Keyboard Warrior said:
You can also try the plastic bag method of putting the plant pot in and sealing a plastic bag around the stem. You only open up very occasionally in order to add some water.
Click to expand...
AFAIK the flies lay the eggs as soon as they emerge from the larvae stage when its something like fungus gnats.

If he already has them they aren;t going away.

They could try nematodes, but you have to be sure you know what your treating because theres different types for different things.

you need to keep it up for like a week or so too

Sand or DE is the easiest way, but if you use cococoir and perlite mix the pots shouldn';t really seem attractive to insects anyway.
 
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You can make insect free soil yourself.

What you do is get your soil from your garden, full of insects. And microwave it.

And the next time one of my siblings does this using my microwave I'm going to go ballistic.
 
arknor said:
things will still crawl int he bottom, even flies


AFAIK the flies lay the eggs as soon as they emerge from the larvae stage when its something like fungus gnats.

If he already has them they aren;t going away.

They could try nematodes, but you have to be sure you know what your treating because theres different types for different things.

you need to keep it up for like a week or so too

Sand or DE is the easiest way, but if you use cococoir and perlite mix the pots shouldn';t really seem attractive to insects anyway.
Click to expand...

Nah its not instant. Like 24-48 hours before they lay iirc.
The plastic bags works fine, I have used it numerous times when I have brought a plant in from outside.
Its really to avoid bringing in contamination for me but I have found bugs inside that were clearly in the soil and they die off.

I have never seen an issue with flies going "in the bottom" but you can maintain a water line anyway if your worried about that.
You should have proper drainage so thats fine anyway

We only normally use DE for a non chemical anti ant treatment.
As they carry the dead back to the nest and eat the dead it triggers a chain reaction.
Don't think it would be particularly effective against eg fungas gnats.
You can get a sort of pelleted version to work the same way as sand in effect that is also DE and it looks quite nice but no idea if its as good as the price would indicate.
Even the old sticky traps can help.
 
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My daughter has used Lechuza PON for ages now and we have had no issue with fungus files or anything else since.
Its initially pricey, needs replacing every 6 months or so, but works.

Planting substrate BASICPON 6 litres | LECHUZA

The planting substrate BASICPON (6 litres) from LECHUZA is free of fertiliser and therefore suitable for particularly sensitive plants.
www.lechuza.co.uk www.lechuza.co.uk
The bigger bags are obviously better value.
 
Last year after repotting a few house plants we were plagued with tiny black flies everywhere. I'm sure it was from store bought soil and not something the cats had left festering somewhere.

The DE is a good shout, it's good for killing ticks too.
 
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