Urea fertilizer - outstanding results

[eds]

If you look at absorption mechanisms, I think it's interesting that while all three nitrogen species can be taken up by both roots and leaves, nitrate and ammoniums are preferentially absorbed by roots, while urea is via the foliar route.

So should we be dosing urea only foliarly (if that's a word!)? It seems some people are having success with it applied to the media/roots. (Perhaps as it's being converted to ammonia then nitrate.)

 

[tomkalina]

Temperature in the growing area has a lot to do with the fertilizer formula we choose. In winter, when our gh temps can get below 60F at night, fertilizers containing more nitrate N than urea are used. In late spring and summer, we switch to a fertilizer that's more urea based because the conversion of urea to the more easily useable nitrate is temperature dependent. The higher the temp, the quicker the conversion.

 

[eds]

So Tom can I ask why are you using urea based ferts if you think they're converted to nitrate before the orchid assimilates them? What do you think is the advantage to using urea?

 

[tomkalina]

We use urea in summer because we've found nitrate based fertilizers are more apt to cause premature leaf loss when combined with high gh temperatures.

 

[eds]

Thanks Tom. I was wondering if there was a cultivation reason or whether it might have been something as simple as cost!