Bonsai pots on grass or stand? Help, slugs and bugs are attacking!

[Hump]

Nuts,

I guess I never thought of this until now. I'm still a newbie, going on year 2 here. I'm having an issue with bugs (mainly slugs, beetles, sap beetles, pill bugs, and worms) getting in my growing medium in my pots. I have a few of my pots on my concrete back porch, which don't have as much of an issue, but the majority are just sitting in the grass and the soil is filled with bugs. Is sitting the pots in grass an issue with anyone else? I would put in the ground, but I'm a renter and I have about 13 trees which would be an issue.

About every month, I normally add a small amount of insecticide in my watering, but it hasn't helped. I've also add slug bait around the pots, but it doesn't seem to of had an effect either. I'm starting to think I'm supposed to put these on a stand or something?

Any feedback would be really appreciated! Thank you!

 

[Brian Van Fleet]

You don’t want them sitting on the grass. Buy a couple cinder blocks and a couple 2x6 boards and make some portable benches.

 

[Hump]

You don’t want them sitting on the grass. Buy a couple cinder blocks and a couple 2x6 boards and make some portable benches.

This makes sense now. Just not something I thought of before. Is it just a common practice rule not to place them on grass?

Only reason I ask is because I remember watching a video from that one prominent Japanese bonsai guy and he had all of his pre bonsai on grass. When he would go and pick one to work on they would have roots coming through the bottom Of the pot and into the ground. I originally thought this was the reason he did it, but with these bugs I'm about done with grass.

 

[Paradox]

This makes sense now. Just not something I thought of before. Is it just a common practice rule not to place them on grass?

Only reason I ask is because I remember watching a video from that one prominent Japanese bonsai guy and he had all of his pre bonsai on grass. When he would go and pick one to work on they would have roots coming through the bottom Of the pot and into the ground. I originally thought this was the reason he did it, but with these bugs I'm about done with grass.

No one I know of puts their bonsai pots on the ground.

As you found out, it makes it easier for bugs to find them. Some will find them anyway even if they are on stands.
Also having the pots on the ground can introduce soil nematodes into the soil of the pot and some of those can be very bad for the tree

 

[Forsoothe!]

If your pots are on the ground they are the ground, just in neat piles. Worms are nice but everything else is a problem at one level or another. Ants are the worst and will occupy the entire volume, happily. A 2 x 6 or 8 or 10 or 12" spanning two cement blocks will get everything off the ground and is mobile if need be.

 

[Hump]

Thanks for the advice guys! Now I'm just anxious because I know I have to repot all of my trees to fully get rid of the bugs. I'll get to work this week in building and repotting.

 

[Wires_Guy_wires]

You don't need to repot to get rid of the bugs.

To get rid of ants in my pots, I soak my pots in a bucket of water and then place them up high. If the ants don't leave by themselves, I put my pot on top of a pot with potting soil. They prefer digging into that. A day or three later they all migrate down.
Nematodes and other grubs usually don't like being up high either, the soil drying regularly is a good nematode killer. Larger grubs can't pass through the pot hole mesh so I don't worry about those.

Slugs and snails are another thing. I can't seem to stop those, but I'm going to try copper tape because I've seen good results.

 

[Bnana]

Nematodes don't care how high up they are and 99% of the nematodes are no problem, they're part of healthy soils. Plant-parasitic nematodes do exist and some can affect trees but in bonsai soil they are hardly relevant.

The main reasons to place a pot higher are slugs/snails and esthetics.

 

[AJL]

Keeping Bonsai on shelving also helps to improve drainage through the pots and improve airflow around the plants
Dont forget that not all bugs are harmful to your trees so do keep it in perspective!

 

[Forsoothe!]

Time to pick a fight about "air flow" in the media. Diffusion is the mechanism that will bring "air" into media as it drys. You can't keep air out of the media even if you tried because "nature abhors a vacuum" and the space that is vacated by one molecule of anything is filled simultaneously with "air". When you water the air space is filled with water and the air is pushed up because air is lighter than water (or anything else). Air exchange keeps occurring as you water, it dries, you water, it drys. It is arguable whether or not more much more air passes through the media if there is a drain hole in the bottom of the vessel or not. There would be some chimney effect as the the vessel heats in the daytime, but whether or not that is more significant as a media cooling device or air delivery system is arguable.

So, some additional air flow occurs through the bottom drain hole during the morning heating up cycle via the chimney effect, but that effect would be static during the other 18 hours of a day. The replacement of molecules of water, et al in the media which occur due to evaporation and transpiration will be by a molecule of air immediately adjacent to the disappearing molecule, which will be replaced by the next adjacent air molecule, ad infinitum and ultimately air moving into the media from any open surface. Since the surface of the pot has hundreds of times more surface area, the net volume of air moving upward through the bottom hole verses downward through the media is minimal, at best, if at all, sans the chimney effect during pot heating.

Anyone arguing against this downward movement of air in a bonsai pot can also explain how the system works on the planet which doesn't have any drain holes.

 

[Leo in N E Illinois]

@Forsoothe! - you are spouting "scienecy gobbly gook".

Air exchange through the potting medium is important. That is true.

All your "reasoning" or "Forsootheing" is confused made up "sciencey" nonsense without any base in science. You sound worse than a "Master Gardener" Dial it back some. Just stop at air movement, air exchange is important for healthy roots.

Time to pick a fight about "air flow" in the media. Diffusion is the mechanism that will bring "air" into media as it drys. You can't keep air out of the media even if you tried because "nature abhors a vacuum" and the space that is vacated by one molecule of anything is filled simultaneously with "air". When you water the air space is filled with water and the air is pushed up because air is lighter than water (or anything else). Air exchange keeps occurring as you water, it dries, you water, it drys. It is arguable whether or not more much more air passes through the media if there is a drain hole in the bottom of the vessel or not. There would be some chimney effect as the the vessel heats in the daytime, but whether or not that is more significant as a media cooling device or air delivery system is arguable.

So, some additional air flow occurs through the bottom drain hole during the morning heating up cycle via the chimney effect, but that effect would be static during the other 18 hours of a day. The replacement of molecules of water, et al in the media which occur due to evaporation and transpiration will be by a molecule of air immediately adjacent to the disappearing molecule, which will be replaced by the next adjacent air molecule, ad infinitum and ultimately air moving into the media from any open surface. Since the surface of the pot has hundreds of times more surface area, the net volume of air moving upward through the bottom hole verses downward through the media is minimal, at best, if at all, sans the chimney effect during pot heating.

Anyone arguing against this downward movement of air in a bonsai pot can also explain how the system works on the planet which doesn't have any drain holes.

 

[Forsoothe!]

Feel free to argue your point and support it with logic/science/BS, et al. Point-by-point. And I am a Master Gardener, class of '79. Not a real botanist, but a real gardener with dirt under my nails and a clear understanding of the principles.

 

[casun]

Air fight! One point to Leo for the use of “scienecy gobbly gook”

 

[LittleDingus]

Diatomaceous earth is excellent for slugs and many soil insects. It can be bought in a fine powder form:

Amazon.com : HARRIS Diatomaceous Earth Crawling Insect Killer, 4lb with Powder Duster Included Inside The Bag : Garden & Outdoor

Amazon.com : HARRIS Diatomaceous Earth Crawling Insect Killer, 4lb with Powder Duster Included Inside The Bag : Garden & Outdoor

www.amazon.com

DE is very sharp edged. It rips slugs causing wounds that dry them out. Fine powder gets between the plates of most beetles doing the same. Ants won't cross it. It's good stuff in the right situation and 100% non-toxic.

It will also kill worms and other good guys. Worms aren't usually fond of typical bonsai media though.