Bonsai Without Chemicals?

[petegreg]

This thread starts to be very interesting. There's other thread in the forum dealing with sifting, grading and layering of different fractions of soil. Some professionals say grade, some don't. Some say use coarser mix for the trees in development and finer mix for finished trees. This may make sense. Where should we go from here?
I use DE earth straight from the bag + zeolite + lava if available. Then I just leave water running through the pot to get rid of dust and the smallest particles. So far so good. Wrong? Here I've found out it can help to keep some pests away,thank you.

 

[parhamr]

So far so good. Wrong? Here I've found out it can help to keep some pests away,thank you.

To clarify: there are at least two forms of diatomaceous earth I’ve seen commonly accessible in the states: “diatomite rock” and “food grade” diatomaceous earth powder. The rock/gravel form is a great potting substrate for bonsai (because particle size, breakdown resistance, CEC, and water-holding capacity) and the food grade powder is a great anti-insect addition to organic-based soil media (because it functions mechanically to dry out and injure tiny creatures which are soft and/or have exoskeletons).

The standard practices of washing and sifting new substrate, plus watering until drainage runs clear, are still advised (AFAIK) for diatomaceous earth rock/gravel. The application of powder is a separate process to the top portion of the soil media, as needed, for pest control and it requires re-application over time. Given the reapplication requirement, simply having diatomaceous earth in the substrate will probably not on its own be adequate to control heavy pest infestations.

In summary: these are similar problems and similar media but not mutually exclusive and generally not invaliding old rules and guidance.

 

[JoeR]

To clarify: there are at least two forms of diatomaceous earth I’ve seen commonly accessible in the states: “diatomite rock” and “food grade” diatomaceous earth powder. The rock/gravel form is a great potting substrate for bonsai (because particle size, breakdown resistance, CEC, and water-holding capacity) and the food grade powder is a great anti-insect addition to organic-based soil media (because it functions mechanically to dry out and injure tiny creatures which are soft and/or have exoskeletons).

The standard practices of washing and sifting new substrate, plus watering until drainage runs clear, are still advised (AFAIK) for diatomaceous earth rock/gravel. The application of powder is a separate process as needed for pest control and it requires re-application over time. Given the reapplication requirement, simply having diatomaceous earth in the substrate will probably not on its own be adequate for heavy pest infestations.

In summary: these are similar problems and similar media but not mutually exclusive and generally not invaliding old rules and guidance.

Interesting, thanks for clarifying.

Anf BTW I did water until it ran clear out of thebottom.

 

[petegreg]

"The application of powder is a separate process"

...so you mean use it as an upper layer if I'm not mistaken. Thank you for explaining, I appreciate it.

 

[justBonsai]

For my application of DE I had tons of little white springtails colonize one of my pots. They don't really cause any harm but are a sign of overwatering. I reduced my water and applied the powdered DE in the soil and the springtails disappeared. Not so sure how well it work against other insects though. Fortunately I don't have have much of any pest issues where I live for any of my trees. Occasionally I apply a systemic for slight fungal issues but that's about it.

 

[One First Matter All]

I do not use any chemicals, but I do use organic sprays including neem oil and pyrethrin. Interestingly, I can't recall any of my bonsai ever REALLY needing it (ie I thought they would die if I didn't treat) but my citrus (in my landscape) DEFINITELY need to be sprayed several times a year or they will die. I have lost two citrus trees to various flying pests, and my landscape hibiscus will occasionally get white fly.

Hey--saw this post from a while back. What ratio neem to water do you use? Also, do you use an emulsifier? Do you find that a neem spray "burns" leaves? I haven't had any issue with burning (yet), but I'm curious to learn more. Thanks!

 

[Bonsai Nut]

What ratio neem to water do you use? Also, do you use an emulsifier? Do you find that a neem spray "burns" leaves? I haven't had any issue with burning (yet), but I'm curious to learn more. Thanks!

Depending upon the material, I use it at full or half strength, but I do NOT use an emulsifier. With delicate deciduous trees like maples I use at half strength, and try to use only as a dormant oil (when leaves are not present). Be cautious about direct sun immediately after treatment - particularly if you are having unusually warm weather.