Fertilizer's "Shelf" Life

This is one of my stupid questions, do chemical fertilizers (powder) lose their effectivity over time? I have a couple of fert in small containers that I can't even remember exactly when I purchased them. The labels are faded and so the color of the fert. They now resemble wet salt and part of it had turned to liquid and settled at the bottom of the container. I know that they are fert for orchids and that they are high in nitro but had stopped using them when I found a fert in 20-20-20 formula. I might have bought this fert in '96 or '97, so they are about 8-9 years old. Are they still good to use? I am thinking of switching to high nitro fert now that most of my chids are planted in pure bark.

Thanks for any advice.

Tanya, if they're that old and moisture has gotten into them, you might want to just throw them out. It may not hurt anything if you go ahead and use them, but water will change the chemical properties of soluble powders once contact has been made, and it's hard to say what the effect might be.

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Louis J. Aszod

Thanks, Lja. I was hoping I could still use them, but what the heck, buying fertilizers is a good excuse to go to the city and visit the Flower Market Rd. AND all those shops full of orchids.