I've heard its best to stay away from using Urea when it comes to fertilizing orchids in general is this true? and why is it so?

I did use a hydroponic fert mix that excluded urea but cannot find anymore.

Also is it best to stay away from using organic ferts like fish emulsions and do these contain urea? Are they too unpredictable, some manufactures dont give a full analysis. I did have the patholygist here look at it and said it was very low in nutrients and not worth using as a garden fertilizer...interesting?

any thoughts?

Cheers
Stephen

I have not used a fertilizer with urea in it, but a grower that I know used a urea fertilizer, and it caused the leaf tips to all turn brown and the tips would eventually die. I do not use a fertilizer with urea because it also seems that any fertilizers that say they are to be used for Paphiopedilums and Phragmipediums also say "Urea Free" right on the front of the bottle. This makes me think that urea would not be the best thing to fertilize slipper orchids with.

Thanks Nick,

Just out of interest, whats the npk on the bottle and brand name?

And I quess Cypripediums dont really like urea as well...Ron,Tom?

Cheers
Stephen

Thanks Nick,

Just out of interest, whats the npk on the bottle and brand name?

And I quess Cypripediums dont really like urea as well...Ron,Tom?

Cheers
Stephen

I use Grow More 20-10-20 Urea free, and I use a 1/3 dosage every week.

Stephen,

Ron can answer this better than me, but here goes my view. Most Cyps respond well to inorganic fertilizers with a low N-P-K ratio and that is fortified with micronutrients. Since this seems to be true for the overwhelming number of species and hybrids out there, why try something else? In my opinion, using a very dilute solution on a frequent basis with adequate flushings with fresh water in between is ideal.

Concerning organic based fertilizer such as fish emulsion, I've heard some folks have good success with it except that you have to remember it is very very mild, so it is easy to under fertilize especially for nutrient hungry species like C. reginae and C. formosanum. Also, this type of fertilizer is a hodge-podge of organic compounds and so is very complex in terms of the breakdown products. Still, with root sensitive plants such as C. acaule, this indeed might be a better choice if you intend to fertilize them. I've never heard of any problems with using this product.

Urea base products are problematic because urea cannot become available to the plant's roots without the presence of bacteria and fungi, so if you are using a soil less mix or have mounted plants most of it just washes away and doesn't feed the plant at all. Also, urea tends to cause algal blooms which can be problematic depending on your set up.

Hi, Stephen,

As usual, Tom beat me to the punch. I echo his comments. Urea is problematic unless one has highly organic medium (which worries me with Cyp's anyway) that can break it down - and even then the rate would be variable. I use ammonium nitrate-containing hydroponics fertilizer.

As for fish emulsion, most are low in urea. While I dont use it on Cyps, Wilford Neptune, who has more awarded Cyp's than anyone else, ONLY uses fish emulsion fertilizer. You can google him using "Wilford Neptune Cypripedium" and see some photos of his award-winning plants and his discussion of culture conditions.

Best,

Ron