troy
Well-Known Member
A balanced 16-16-16 fertilizer at 1/4 strength alternated with a cal mag 15 - 5 - 15 jacks brand at 1/4 strength works for me, I'm not saying that to argue, just saying thats what works for me
Water is truly the driving force for plant growth; fertilizer is far less important, but residues in the pot can inhibit plant growth. And while I agree there will always be buildup in all media, the use of very low fertilizer concentrations, while not only closer to what the plants see in nature, will slow the accumulation. Keeping the medium moist also helps prevent precipitation.Also vitally important is to get a feel for what is going on in the pot. Nutrients usually build up over time regardless of how low the concentration but not just that, certain fungi build up as well if the pot is not full of roots, these fungi kill roots. Not directly but probably some exudation from them. It's what is normally referred to as stale mix. To prevent this you need to leach by flushing out with a strong and sustained stream of water 2 or 3 times in one day one hour apart. (if you're not sure that the pot has been flushed well it probably hasn't) This seems to wash out all the crap including salt build up which inhibits healthy roots.
Yes plants need P for root production but they need it just as much for the whole plant. The old claims that P is for root growth is not true. In other words, giving more P than is necessary for the normal growth of a plant will NOT increase root growth. It has been tested in trials a number of times. But yes I agree that any standard fertilizer off the shelf of your favourite hardware store will give you the basic NPK that you need. 1-0.3-1 or 10-3-10 is about right..Yes plants need P for root production but they need it just as much for the whole plant. The old claims that P is for root growth is not true. In other words, giving more P than is necessary for the normal growth of a plant will NOT increase root growth. It has been tested in trials a number of times. But yes I agree that any standard fertilizer off the shelf of your favourite hardware store will give you the basic NPK that you need. 1-0.3-1 or 10-3-10 is about right. I use these types and add my own mix of trace elements which includes Ni which is vital if you use Urea.
I agree entirely with this.I think that there simply hasn't been enough research into the nutritional demands of individual orchids for anyone - including you and me - to say for certain what formula is "perfect" for what plants, and it can vary all over the map.
My experience is the same but I was not using K-lite. I used a 2:1 (N:K) ratio for vandas and cattleyas. The vandas became lanky a bit but some cattleyas had soft stems/bulbs and were quite stretched that they bend over. I caught then just in time and shifted to low N. I noticed the big clumps on a wide pot full of big barks did not show any of this. But I was watching the back bulbs if they start dying.I agree entirely with this.
I ran a fertilizer trial many years ago using a K-Lite equivalent fertilizer over many different genera, and they all had different results. Cattleyas were out of control, hard cane dendrobiums new growths was too soft and collapsed in our hot weather. I stopped the program 2 years after starting because I couldn't keep up with repotting and dividing Cattleyas every year.
Diluted at 1:250 and applied monthly, KelpMax contributes 28 mg K per month. K-Lite, when applied at 75 ppm N weekly, contributes about 12x that, making the KelpMax contribution only about 7-8% of the total. I seriously doubt that's the "make or break" factor.Ray, you have a good source of K from KelpMax. It just not advertized.