Hard soil on top layer question

[Headhunter843]

The top layer of soil on my Trident Maple forest is very hard and compacted. I purchased this a month ago and it was in the same condition at the nursery. A nursery worker poked some holes in it while watering, to aid in the water uptake before I left with it. My plan is to add a larger Trident as the dominant tree and repot it this coming winter into a larger pot. The trees appear to be healthy and growing, so should I worry about the concrete patio on top of the soil in the meantime or just let it go and deal with it when I repot?

 

[Deep Sea Diver]

Welcome Aboard Bonsai Nut!

Two thoughts….

Do Soji now - This means get a chopstick(s) and scrape the media outward from each trunk, removing the top layer of encrusted soil. This works best when the issue is caused by skyfall, weathered media and dead plant debris at the surface causing compacted soil. Then replace with fresh media. Usually need to remove 1” of media or more.

However in this instance one wouldn’t want to go much more than this considering the pot size.

The other method, which can be used in conjunction with soji, is drilling. Given the amount of tridents and their age in is this pot, it’s more than likely both might be needed.

Drilling holes is a good stop gap measure for a compacted root ball. We usually use 1/8-1/4” long drills to drill diagonally into the rootball, (outside angled inward) to increase water penetration into the shin. Any drill will work, although concrete drills with a more rounded tip seem to work best. Do not force the drill, let it find its own way around roots etc.

The number of holes varies. Likely that pot would need somewhere between 8-12 depending on the size.

When repotting, one might consider putting the composition in a forest training oval to let the roots run sideways vs down.

btw: Please click on your icon atop the page, then account details and enter your approximate location and USDA Plant Hardiness zone. This data is invaluable for folks trying to give helpful advice.

Cheers
DSD sends

 

[Shibui]

Agree with the above as short term measures. It appears this one has not been repotted for some years so the pot is likely to be filled with roots, making the soil feel hard but also making it difficult to water effectively. If you find the trees begin to droop as the days get warmer I'd soak the pot in a tub of water once a week or so to make sure they soil gets properly wet occasionally.
Proper repot will be the solution longer term.

Where do you intend to add the new tree? Have you done similar before? That's likely to require a complete dismantling of the current group which is possible but can be a daunting prospect for a beginner.

 

[Headhunter843]

Thanks for the responses Deep Sea Diver and Shibui. I had not thought of drilling and will scrape off the compacted top layer tomorrow. Shibui, I have never done this before, so it would be my first attempt. What the heck! Might as well go for it!