Anyone with experience using "High Pressure Root Propagation Balls"?

Hi folks, I know you've all seen in your FB marketplace feed over the past year the "High Pressure Root Propagation Balls" that the dodgy sellers are sponsoring ads for.  I hate to give my money to Bezos, but with Amazon Smiles I certainly feel safer trying these out knowing that I will actually receive them.

Anyone have experience with these?

I am thinking if using them on  my best apple trees before pruning.  I know that rootstock is the best for grafting and yada yada yada, but with consistently high performing trees, what would I  lose other than a few dollars in trying these on the larger pruned branches I want to do?

I am also thinking they might come in handy for blueberry bush propagation too.

What say the Permie community?

Thanks in advance,

Mark

Frog Hollow Schoolmaster's Homestead
Myersville, Maryland
https://facebook.com/froghollowhomestead
https://www.FrogHollowHomestead.com

I have used a similar root ball system on a Canadian choke cherry with success. After looking at them II achieved the same success with a 16 oz soda bottle split down one side and taped closed. I used a horse syringe with water to squirt into the moss potting soil mix as I did my daily fiddling, letting the ball get dry diminished my success rate.

Robert Ray wrote: After looking at them I achieved the same success with a 16 oz soda bottle split down one side and taped closed. I used a horse syringe with water to squirt into the moss potting soil mix as I did my daily fiddling, letting the ball get dry diminished my success rate.

Thanks a bunch Robert for your reply!  Since you use a soda bottle, I assume that the bottle being transparent is not a problem for the developing roots (since they are enclosed in soil too).

During the Pandemic we receive food from the local school (USDA grant for *all* children) and the meals come with small 6 ounce chocolate and regular milk containers.  The milk is packaged at our local large dairy packager in Frederick (Dairy Maid) so the food miles is close even though the packaging is hideous (especially at our scale as we have 10 children, ages 2y to 16y).  Instead of recycling these containers, I am thinking I can use these as an appropriate sized root ball propagator, especially for my blueberries.  We get so many of these (3 meals a day x 10 kids x 7 days a week) that I can cut them in half and use them clamshell together - see pic.

Should I wait until my typical pruning time (Jan-Feb) or would it be ok to try some now - or, do I need to wait until the danger of freezing is mostly past (I am in Zone 7a - Maryland Blue Ridge) in case a freeze through the soil and root ball propagator can kill the developing roots?

Thanks again for the advice!

Mark
Frog Hollow Schoolmaster's Homestead
Myersville, Maryland

That looks like a perfect container for propagating.  I can't answer to the freezing of the root ball my trials were during the spring and summer.