Root pruning will lilely stunt growth more than it would stimulate it. When the larger main roots are broken severely, a lot of times that whole root will die which can really hurt a palm. I think that people overstate how sensitive palm roots are because I believe they can recover from root damage, but root pruning is definitely not something I would risk with palms. Other potted plants like hibiscus can be root pruned since they are plants with lots of stems so any damage will be followed by recovery. Palms only have 1 growing point and it's sensitive to a lot of change depending on the species.
-Alex

Agree with Alex. But at 20 gallons, and unable to plant outdoors, why would you even want them to grow any bigger or faster? When my tropical palms got too big, I had to give them away or let the die.

Hi
have been doing that for a number of years . Primarily to keep them dwarfed Followed general "Bonsai procedures .
Could not keep them under 6 feet so gave up. The best results were with packed long fiber sphagnum moss . failed to develop trunks and remained immature.
How large do you want them to get?? gary

I'll take the suggestions and not root prune. I don't want them to necessarily grow taller or wider, just to replace some of the older fronds that look fried due to...sunburn, cold damage, age, and drought damage etc., after a year's time. I think part of the problem was just keeping the root ball moist with the hot/very dry weather. I think the situation will be improved by adding a few inches of fresh soil to the bottom and mulching the surfice with a healthy layer of moss. Got to believe it's going to be raining more too. Steady, natural rains are just much better than a quick hose down, as has been repeated here time and time again.

palms do not like roots messed with. there is no situation, other than trying to bonsai a palm (not always that easy) to root prune a palm, other than to make it weak or slow down or die.

I feel your rain pain. It's been even dryer here.

I understand what you're trying to get at, with some of the ratty, old burnt fronds. Double-edged sword. If they're still green, they're feeding the plant. But if they're ratty, they probably make it look unhealthy. If it's root bound and not much soil left, that is probably why it's not growing. At 20 gallons, I'm not sure what to recommend. You certainly don't want to go up to 30 gallons, unless you own a conservatory. Augment the soil, with a fresh bag of potting soil? Increased fertilizer in diluted, but frequent feedings?

I have no direct experience with root pruning, but Queen palms, being fast growing, IF they tolerate the root pruning, will quickly fill the pot with roots again and you'll be right back where you started. I would be inclined to remove the ratty fronds, water thoroughly, then fertilize. Most palms are container tolerant in the extreme -- but again, I have no direct experience keeping large palms potbound.

One suggestion I would make, with your next potted palm project, select a slow growing palm. Queens are rockets; maybe you need a burro. :-D I know a woman in Sweden growing a Hyophorbe indica exclusively indoors. She's had it for perhaps 8 years, germinated from seed, and it's just now starting to brush the ceiling, and it's absolutely gorgeous! Maybe a Kentiopsis oliviformis would do well for you? Any of the palms that people complain are slow could be reasonable indoor candidates, except for ultra-tropicals in the category of Cyrtostachys renda and the like.

In any case, good luck with your Queens, I hope they perk up for you.

I have a couple of Hyophorbes (Spindle and Bottle Palms). And although I like them, I like the Queens better. Something about those graceful fronds in a breeze. They really remind me of Roystoneas ( of which I have a smaller specimen), one of my favorite of the pinnates by the way. The Queens are actually looking better already. I will leave on the still green ratty leaves as they are still photosynthesizing and making food for the plant until it takes off. Burro palms would make a nice acquisition. Thanks!

Holy thread resurrection Batman! Just found this post. My 2 cents:

Not sure if this is feasible for you, but I would suggest sitting your pot directly on top or even submerged an inch or two over some soil on the ground. Some roots will escape the drainage holes and contribute to good seasonal growth.

At some point in the late summer or fall, use a knife to prune back those roots back to the drainage holes and let the plant spend some time outdoors "recovering". There's no reason the palm should suffer any setback since the majority of the rootball remains intact.

The following spring, rinse and repeat.

I do this with most of my cycads and big tree aloes, all in pots. Aloes can be abused easily without harm - I have 6-ft tall A dichotoma and A 'Hercules' with 6+ inch trunks this way.. I only have one true palm, a nice sized Hyophorbe lagenicaulis (Bottle Palm) but it is still growing nicely in its pot. When I see growth begin to stall, I will do the same with this as I suggested earlier.

Good Luck!

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