Viewing post #3077256 by MoonShadows

Gina1960 said: Its important to know the difference between Osmocote and Nutricote (aka Dynamite) slow release fertilizers. It may help you decide which one to use.

Osmocote is a controlled release. What 'controls' it is the temperature of the soil. It needs to be around 80F to start releasing, and it does it because molecules in the little balls expand at that temp, and when water hits them, they release. If the soil temp is below about 80F, Osmocote will not release. It just sits there. That makes Osmocote my choice, because I don't actually WANT all my plants to be getting a hit of nutrients in the cold months.

Nutricote (Dynamite) is a chemical release, not a controlled release. It isn't dependent on the temp of the soil. Whenever water hits it, it will release. SO every time you water its releasing a bit.

That makes Osmocote more cost effective for me, because its not releasing in the winter and getting used up when I don't want it to be releasing.

Thanks for that explanation, Gina. I use Pro Mix Organic Seed Starter. I don't plan to use the Osmocote until I up-pot which won't be for at least 6 weeks. I only plan to use the Osmocote on these up-potted plants that will be staying in the greenhouse. By then, 80 degrees is not problem. Even sunny days now, 80 is no problem in the greenhouse.

Cloudy, cold days like today, 44 degrees and winds in the teens, my greenhouse is at 71 right now. This new greenhouse holds the heat so much better than the old one, especially with the pond, brick floor, and Phase Change Panels.