Restarting my bonsai journey, soil mixture question.

[Pitre]

Years ago I got into the bonsai hobby, and let’s just say for “reasons”, I lost the few tress I had. 15 years later I have the itch again, so I’m starting over. A beginner once again.

My question is about DIY soil mixture. I know it gets asked a million times, and that is part of the problem. I’ve been reading for over a week now and it’s hard to decide what is right and what is wrong.

I was hoping to find someone here on the forum from the South East Louisiana area to see what local nurseries or big box stores offer that you all are using. It seems like I would like to use a mix of pumice or perlite, lava rock, and some form of organic soil. The argument over whether pine bark is good/not good, should be composted/ not composted. Some say orchid mix or fir is better than pine.
I know from last experience some of the potting soils you buy seem to form a crust like layer on top and the water has trouble penetrating. Obviously I don’t want that, but I’m not sure what makes for that type of soil.

I currently have two willow trees and a China ball tree (wax Myrtle I believe), all three collected from family property, and a Chinese elm. The elm is in the soil that it was shipped in from Brussels. The locally gathered trees are doing well in the soil I currently have them in. They are budding and starting to push nice leaves out as spring rolls around.

Sorry for the long winded post, but thank you to anyone who chimes in.
Clint

 

[Shibui]

My question is about DIY soil mixture. I know it gets asked a million times, and that is part of the problem. I’ve been reading for over a week now and it’s hard to decide what is right and what is wrong.

I'm not from your area so hope some locals chime in to add their 2c worth.

IMHO, there is no right and wrong soil which is probably why you are having trouble finding consensus.
The 'right' soil for you may not be 'right' for someone else if they care for their trees slightly different. We all need to find a soil type that copes with how we water and care for the trees and for the local conditions. I've heard of many beginners who changed to a recommended soil mix, only to find it did not suit their care and conditions with resulting losses of trees.
Remember that local conditions can vary quite a lot from one side of the street to the other and one side of the hill to the other so it is likely you'll still get dissent amongst relatively local growers.

The elm is in the soil that it was shipped in from Brussels. The locally gathered trees are doing well in the soil I currently have them in. They are budding and starting to push nice leaves out as spring rolls around.

The fact that your current trees are doing well in the soil you already have is probably a good starting point. Try to work out what materials are in those soils and start your trials based on that info.

Some parameters to consider:
Inorganics tend to decay very slowly so those soil mixes last longer term. Some can be sieved out, washed and reused.
Inorganics may be expensive depending where they are mined and processed.
Inorganics may not hold much moisture so you may need to water more often or problems with dehydration until you find the balance.
Inorganics tend to drain faster so may have less problems with root rot, especially good for those who tend to over water.
Only a few inorganics hold nutrients well so generally need to fertilise inorganic soils more regularly.
Organic components break down over different timeframes (depending on the product). You'll probably need to repot a little sooner when using organic based soil mix.
Organics may hold nutrient a little better than most inorganics = less fertiliser application?
Organics tend to hold more water. That's a 2 edged sword. Less watering required but sometimes also more root rot problems if you don't manage watering to match the soil.
Some organic components may be cheaper if they are produced locally.
Some organics can initially 'lock up' nutrients so they are not available to the plant. May need to add extra nutrient to counteract this when using fresh mix but nutrient balance usually returns after a few weeks/ months.

 

[Zac]

Yeah it all depends on you and your care habits. I tried switching to inorganic soil but my trees struggled some died because of my long work days I can only water once early early morning then late evening when I get home they would be completely dried out and is have to water again. With the organics I can water once in morning on real hot dry days twice and my trees did better. Now in the spring and fall if rains alot have to pay attention so don't get soggy. I'd lay pices of broken tile or slate over soil. I do know peat based soils are a big problem.

 

[Gabler]

It seems like I would like to use a mix of pumice or perlite, lava rock, and some form of organic soil. The argument over whether pine bark is good/not good, should be composted/ not composted. Some say orchid mix or fir is better than pine.

Any of these options should work. Just pick one and try it out. If it's drying out too quickly or too slowly, adjust accordingly.