@Izzyi2d Suggestions....hmmm. More space to grow in? :p
@Stumpy420 Very nice! Each of your runs are looking better and you can't beat that right?
@BlackSheepOG Nice flower, roots and 'does' phat wurms.
Bit of an update with Veg NPK's. I'm comfortable enough to convey a working formula for long-term no run-off.
This bull was grown in my 16oz cups. Watered once per day, no run-off no flush for about 8 weeks from 2" rooted cut. 4 weeks of that under 40w LED and 4 weeks under 150w vertical hps. No training or trimming. Appx. 6" x 6" grow space lol ( 8 in 24" square).
Based on watering daily with no run-0ff:
*Lowering the K value in relation to N virtually eliminated purple stripes and petioles (assuming happy roots and root environment). Note that this is separate from photoinhibition related coloration.
*Lowering the P value in relation to N increased rooting speed and maximum density. Also overall root health.
Starting point for NPK testing was the standard 3-1-2 ratio which virtually all vegetative plant tissues correlate. Note that 3-1-2 ratio, as is referenced, is relating to % weights and NOT ppm ratio. A 3-1-2 ratio in percent is equal to a 100-15-55 NPK ratio in ppms. Those ppm's correspond closely with actual measured uptake values are, relative to N.
--The working formula ATM is: 120-23-90-70-20-22-1 (N-P-K-Ca-Mg-S- Fe).
This has proven to be plentiful if not still excessive P and plentiful amounts of K. There are excesses of Ca,K,P,Mg and S, but I still have to allow for medium CEC. This is for long-term with no-run off required. Testing run-off after 6 weeks averaged 1.8 EC and after 8 weeks averaged 2.1 EC. Not recommended for flower or stretch though.
If anyone is running chemical nutes and would like to see if lowering K:N will lower purpling for them; I highly recommend trying it. There are 2 companies that offer 3-1-2 ratios in the hydro industry. Foliage Pro 9-3-6 (with Fe) @ 4ml per gallon or CNS 17 Grow 3-1-2 (No Fe) @ 14.5ml per gallon.
If anyone is running the standard Veg ratio's used commonly for MJ, you can easily water "a few times" with a 3-1-2 and I bet you will see improvements. Long term, a ratio closer to above would be recommended. *This is based on soilless mediums (coir and/or peat tested)
Sorry for the ramble