Urea

Hi Dess, what you read is right. Urea is potentially a very dangerous chemical for orchids only when you consider conventional growing. I fertilize my orchids with urea but only as a foliar spray at the rate of 75 ppm (75 mg/litre). Urea is bad when used at high doses (^200 ppm). Urea at 75 to 100 ppm is beneficial for orchids and most plants. One of my friends in the orchid industry tells me that it is a ingredient of the foilar spray they use on Phalaenopsis, which makes the plants grow and flower about 30% faster. Just avoid using it as the sole source of nitrogen.
If from the 300 mg nitrogen supplied by 1 gm of your fertilizer, 100 mg is (~30%) is from Urea then it should be just fine.
But urea is a strict NO if you are growing your orchids in Semi hydroponics or in a completely inorganic media.

I agree.

I've used plain old Urea-containing Miracle grow on my orchids at low concentrations with no detriment. Just mix it at half strength and you should be fine.

Originally Posted by clintdawley

I agree.

I've used plain old Urea-containing Miracle grow on my orchids at low concentrations with no detriment. Just mix it at half strength and you should be fine.

I also agree!!

Cheers,
BD

This is so helpful! I have read many reports not to give urea. The rationale that I read states that urea requires the activity of soil bacteria to break down into a form that plants can use, and as epiphytes growing in nonsoil medium the orchids don't have the benefit of soil bacteria. On the other hand, most of the grow-type orchid foods that I have located contain urea. I suspected it wasn't that simple, and that the bacteria may be present in bark medium, but who knows? :-)

Anyway, it's good to see that others use the urea-containing fertilizers without harm and probably with benefit. I'll feel better about using it this year. I think I'll bet faster and better growth this way.

Thanks for this discussion even though it is old. It's very helpful!