Just ordered 45# of 3/16" Pumice from http://www.generalpumiceproduc...

Unable to find locally & "WANT" to believe Pumice is better than Perlite in my Plumeria potting mixes... If for no other reason, it _won't float to the surface... Plus help weigh down my 10 gallon squat pots from wind damage..

Do you think I'll need to add sand to the mix too? I'm mixing up a 100 gallon batch using Miracle Grow Cactus mix as the base..


getting ready for the Spring 2019 repot-a-thon

I'd say no sand, Glenn. I like pumice better than perlite too, for the same reasons. I also object to the bright white of perlite. Finding pumice is tough. How was the shipping on it?

plantmanager said:How was the shipping on it?

FREE Shipping

Wow, I've never found a place like that. Thanks!

with Karen, I also prefer pumice much more than perlite. And, no to sand as well.

That is a good source of pumice! Thanks for the link Glenn!

Thanks for this! I love the idea of adding weight to a pot as my taller pots blow over on occasion. Not fond of the way perlite just never disappears, washing away from pot surfaces, floating here and there. Can you give a gal a clue and tell me approx what 15# of pumice looks like say, compared to a bag of 40# fertilizer? I buy giant bags of perlite at HD and go through 2-3 a year.

ShadyGreenThumb said:Can you give a gal a clue and tell me approx what 15# of pumice looks like say, compared to a bag of 40# fertilizer?

From their website, it looks to be around 3 gallons... since it fits in a USPS Priority Mail Flat Rate shipping box.

Just purchased a #24 bag of Lava from Hawaii since they have a surplus at the moment.

https://www.amazon.com/dp/B004MX921O/

I know, I'm going overboard on this Plumeria Mix... but I want my Plumerias to do the Hula.

This will be added to the #45 of Pumice & 50 bags of Miraclegro Cactus Mix for my 10 - Ten Gallon pots.

Looks good Glenn!

I always have to stake my Plumies here, we also get quite windy at times. Do update us how your Plumies go next growing season!

I stake leaning branches, as well. How do you stake them in such porous soil?

Composted Soil with Coco Coir and 50% Pumice. Your roots will thank you. I use it for all my container plumerias and they do excellent. Water runs out almost instantly.

ShadyGreenThumb said:I stake leaning branches, as well. How do you stake them in such porous soil?

I've used Bamboo stakes, but they're kinda flimsy.. Ordered these: https://www.homedepot.com/p/Vi...

Impressed with the Sturdy Viagrow metal stakes...

I like those stakes, too @BBQNBLUES. I have some bamboo from my GF's trees. They work because I can get stakes 12 f tall for some of those lanky limbs. But in the porous soil, it your stakes stay put?

I have never used pumice. I actually prefer to use packing peanuts. I use the packing peanuts I get from mail order stuff in place of Perlite. I use it in the lower layers of the potting mix. I 'restart' a lot of rootless rhizomes of gingers and heliconias, and in the cooler parts of the year it is extra important not to have the soil retain water so rhizomes don't rot. I have used a mix of 1/3 peat moss, 1/3 orchid bark and 1/3 Jungle Growth (tm) potting mix with the extra addition of packing peanuts for years. It never fails me. I root plumeria in it too

I've used packing peanuts in pots before but I always regret it when it comes time to repot.....

Ditto that, Hetty. Packing peanuts don't decompose but roots wrap around them and make it impossible to untangle. But in a large pot, it sure keeps it lightweight.

For my own purposes, I actually do not WANT them to decompose. Its a good thing for me when the roots wrap around them and go through them. They fulfill a really necessary purpose for the particular plants that I grow of creating larger air spaces the keep the soil from compacting around the roots and getting to boggy over time, which can cause root rot in containerized plants of these types. The alternative would be to use a like amount of hard nut shells (growers in Australia favor macadamia nut shells) but I do not have a source for obtaining those in high quantity. The use of orchid bark with the chunks of charcoal and LARGE perlite pieces is almost as good but costs a lot more, and the use of old wine corks is also beneficial. The best things I ever found was to use the little expanded clay pieces that are used a lot for orchids, but these get expensive and if you are looking to lighten up pots, they will not do that. But they do have the advantage of absorbing water and slowly re-releasing it.

I sometimes use LARGE chunks of styrofoam when I have a big pot and I want to avoid it becoming too heavy.

Has anybody used large oyster shells? I have access to sacks and sacks of these for free.

I am not sure that oyster shells would be good long term, they might leach too much calcium into the soil