It doesn’t need that much water, but it certainly likes things very moist.
The original plan was to do a 50/50 compost/peat moss. I’m not adding vermiculite because peat moss has a bit higher water-holding capacity, and the fact that this plant likes acidic soils lets me get away with using a ton of that. But I do have a bag of those hydrogel water beads. Has anybody used them mixed in soil for water retention?
Bonus pic: the sweet gale was sitting next to this water hemloc, dubbed the most violently poisonous plant in the North American continent. But it is so pretty.
Are you in the native territory of this species? If so, it shouldn’t be necessary to go quite this all out. It will be necessary to water very regularly for the first warm season in the ground, and I recommend mulching heavily on all moisture-loving plants. What they really want is consistently high moisture and cool roots. Bear in mind that aeration is just as critical as moisture. The whole Myrica genus love water, but they also need oxygen around their roots. That mama plant is in a living, cycling ecosystem, not just standing water. Oxygenation is happening. Waterlogged and poorly draining soils risk turning anaerobic and rotting your plant. I’m from the part of the country where they literally make bricks for construction out of our ‘soil’ and Myrica cerifera is happy as a clam here as long as it gets regular water and/or has really deep mulch. It grows both down in the streambeds and up alongside the foundations of houses.
If your existing soil is very well drained then yes, it would help to add some moisture retaining organic material… I would go with composted leaves and a heavy mulch though, not peat or hydrogel.
I have got the gel left over from “hello fresh” ice packs - sodium polyacrylate. It absorbs 300 x water. I don’t want to take the stuff to the dump -it’s heavy and seems wasteful. I don’t want to put it in my septic. I was dumping it in one spot outside and that spot was like a skating rink after a few weeks. Stayed moist and since I was just dumping it on top it was like a slushy pile. So I’ve been drying it and thinking about using it to amend potted plants. or sandy soil??
thoughts? I don’t care about whether it’s safe for growing food - this would be for ornamental plants.
I don’t remember the actual numbers but of the common stuff, peat has the highest water retention value, followed by compost. Top of my head it think peat can hold 30 times is weight in water. Hydrogel on the other hand can hold 200–600 times is weight in water.
Waaaaay back in 2018, I placed an order for some bareroot plants from Indiana Berry along with a 4 oz packet of their “Start-R-Gel” product, which I believe was repacked “Soil Moist” (or some other similar product); when I rehydrated it, it looked like this:
The product sheet for Soil Moist here mentions that it’s a “synthetic acrylic polyacrylamide with a potassium salt base” and you can safely mix it with your soil for increased water retention.
I will note that there is caution against using soil amendments like this, outlined on this University of Washington blog post and the linked articleon hydrogels. Key highlights (in my opinion) include the hydrogel causing nutrient deficiencies as it breaks down, possible acrylamide contamination, and fatal impact on fish and other aquatic life. They advise you to use natural soil amendments (peat, compost, etc.) to improve water retention instead, which I think makes sense given the risks!
It seems to me that more research is needed on how helpful it is to plants.
The downstream affects on aquatic wildlife seem a bit overblown. It looks like they dumped a huge amount into a small system. Considering the affects of x-P-K fertilizer are awful for fish, and we use that constantly, I don’t think the “risk” is unreasonable. I will note that the FDA has approved sodium polyacrylate (in small quantities) for drug delivery.
I am not opposed to using only natural materials - but they can be harmful too. I’m just curious if this stuff has a use in growing things - and it seems like the answer is “maybe”
Sorry. re-reading what I wrote it sounds more angry than I am! I am really just curious to know what I can do with a large pile of gel stuff. I’m really not opposed to natural things - but also not opposed to chemicals. I hope that makes sense. I just want to know what works.
Yes, I think that makes sense! I didn’t take your original comment to be abrasive, I agree that we should be open minded when it comes to new technologies/chemicals/options since sometimes they’re better than the alternatives. If we rejected every new thing, we’d be eating some pretty gross fruit! Just gotta do enough research to make an informed decision
Yes, but 200 times its weight in water is not necessary, especially not when the product comes with a lot of environmental risks. Organic material actually improves the soil as it breaks down and gets naturally incorporated into the ecology. Hydrogels break down much more slowly and release their components into waterways. Check out the paper here from the National Center for Biotechnology Information. I suggest reading the whole thing, but particularly section 2.6: Summary of How Hydrogels Influence Soil Hydraulic Properties. This is a quote from the abstract:
The application of bio-based and synthetic hydrogels both decreased saturated hydraulic conductivity, reduced infiltration, and decreased soil evaporation.
My only issue with peat is that it’s a limited resource and we should generally be trying to cut back on it wherever there’s an acceptable alternative. I use it in my greenhouse where I can limit it, but absolutely not as a soil amendment, where it would take a huge amount of material to make a real difference… And then it might wash away in the next downpour.
I don’t know, the warnings on hydrogel are what I would expect. It holds water like crazy, so I would expect it to decrease saturated hydraulic conductivity, which would lead to reduced infiltration. Decreased soil evaporation would be another given. Another type of soil that would describe that to a T would be heavy clay content.
I would expect a reasonable amount throughout the mediums would help, just like a reasonable amount of clay can help some soils.
Yeah, using it in moderation with loose distribution is a good idea… But wouldn’t it be better and cheaper in the long term to just add organic material and improve the soil quality? And the hydraulic conductivity is critical to plants actually taking up nutrients.
The medium I’m going to use is pretty much all organic material already.
I (and the rest of the valley, 20 miles wide and hundreds of miles long) am sitting on an ancient glacier moraine/river bed. The native ‘soil’ is nothing but rocks and river gravel. Basically this plant will get a 1 foot deep by 2 feet diameter planting hole filled with the soil I’m making for it. Funny enough the volume of that is 3.14159 cubic feet, which happens to be the value of PI.
Long story short: it is a limited amount of soil to be tailored. Peat moss can hold 70~80% of water by weight. compost is not far behind. Hydrogel can hold around 300 times its weight in water, which means that a pound of hydrogel is just a small amount by volume but adds an incredible amount of water retention. And because it is not that much (by volume) there is plenty of other material to keep things flowing.
By the way I also like to spike my soils with woodchips. Water retention is OK (50% by weight), it does have some nutrients that eventually break down into the soil, but their contribution is a pretty significant bump to the Cation Exchange Capacity of the soil.
