Do you know how long these crystals last in the soil.
1806437
Everyone should read the article from Washington State University, http://puyallup.wsu.edu/~Linda Chalker-Scott/Horticultural Myths_files/Myths/magazine pdfs/MythsHyd. It thoroughly explains all aspects of PAM (polyacrylamide) --effectiveness, uses, health and environmental hazards, longevity. Everyone should know that the cationic form is hazardous to your health and the environment and that in higher concentrations may be carcinogenic. An international study recommended .1-.5 ppm (parts per million) when used in cosmetics; in comparison the U.S. allows 500 ppm for agricultural PAM. Polyssacharides gels were recommended as a safe and more effective alternative. Everyone should read the article from Washington State University, http://puyallup.wsu.edu/~Linda Chalker-Scott/Horticultural Myths_files/Myths/magazine pdfs/MythsHyd. It thoroughly explains all aspects of PAM (polyacrylamide) --effectiveness, uses, health and environmental hazards, longevity. Everyone should know that the cationic form is hazardous to your health and the environment and that in higher concentrations may be carcinogenic. An international study recommended .1-.5 ppm (parts per million) when used in cosmetics; in comparison the U.S. allows 500 ppm for agricultural PAM.... » Read More Everyone should read the article from Washington State University, http://puyallup.wsu.edu/~Linda Chalker-Scott/Horticultural Myths_files/Myths/magazine pdfs/MythsHyd. It thoroughly explains all aspects of PAM (polyacrylamide) --effectiveness, uses, health and environmental hazards, longevity. Everyone should know that the cationic form is hazardous to your health and the environment and that in higher concentrations may be carcinogenic. An international study recommended .1-.5 ppm (parts per million) when used in cosmetics; in comparison the U.S. allows 500 ppm for agricultural PAM. Polyssacharides gels were recommended as a safe and more effective alternative. « Show Less
1806438
I do not. Sorry - I purchased them to make neck coolers for military service dogs!
1806439
We have used this type of polymer crystals for decades and know that they have a very long life. We tend to add more every couple years, but that is mainly because some is lost when we remove plants. They balance the moisture for plants, especially in containers on decks and rooftop gardens, and our yields are always better and healthier. Some commercial farmers purchase boxcar loads and use them in fields in areas where water is scarce.
1806440
I've only used the crystals to hydrate fabric neck coolers. Even on a hot day, the neck cooler will stay plump for 10 to 12 hour. No other substances are added, only the crystals.
1307088
I think they will last that long with no problems. I keep mine in a sealed bag and soak in a weak fertilizer solution before I use.
1424172
yes. you should mix the crystals in the soil, not just pour it on top. also be aware it expands a lot when watered. try taking half a teaspoon and put in a bowl and add water and see how much volume it adds, and take that into account when adding dry crystals to the soil...
1111832
I am not sure the crystals this has is the same as what I get, but they work just fine. I buy them at the only local grocery store that carries them, so I only go to that store. I've seen them advertised in pet supply stores, but I sure wish more people carried them!
1389694
They are still in the garden shed - won't plant them until spring. The most important thing to know about them is that they are plastic, not clay.
473865
I just checked a box I have and they have a June 2014 date on...so guessing a year or so, but they never last that long in my house!
2208134
It depends on how heavy the usage is on your system. They usually last about 3 to 4 months with our system.
800564
Haven't an answer for the sandy soil, but can tell you the batteries last at least 4 month. In fact I missed taking the batteries out last fall, and this year when I put it in, it was still working.
2109979
If they got squished between a tire and a hard enough surface, they'd degrade quickly, definitely squish, possibly explode. The crystals feel like Jello when they're saturated; I think you'd just be making expensive mud.
484425
Yes. It's a tri-colored (brown, white and teal) granular product that will sit on the soil, until dissolved by watering or rainfall. =)
219167
Like 15-20 days, but mines died after, i think they dont grow good in my region. Dont store it long time.
251174
I covered mine with sand . I'm not sure what the crystals are . I really haven't tried it yet . I live in Florida and we are waiting until fall .
71929
If kept in a cool, humid free area they can last for years. If I remember correctly I'm thinking 10 years +/- a year or two.
1984982
We have been using about a dozen for 6 months no problems. I would think the would last several years because they are LED. The plants seem to respond well.
1261292
they are like rock salt crystals but about 1/8 in long. They do fizz. Sorry did not see Moon Struck.
1947501
They are 6" long and work great if have some clay in your soil. Not so good in 95%+ sandy soil.
780236
They will likely out live life on earth. Eventually the minerals will erode back into the soil, but by then there will be no one left to use them anyhow.