I’m earthboxes and reuse the mix too. Corrections are made with salts quite often to remove the guesswork and avoid na,Al,chloride etc. microbes get over it. When you have enough ca you’ll see swollen nodes no more than 3-4 branches below the tips. Those smaller red stems on your 15’s are showing low ca/p.
You're saying I need to get the P up right? That's my thoughts at least.
I see Low ca and p and they’re out of balance. Once you get enough ca balanced with p the metals will stay proper and smaller amounts of k will be needed. Look at ca as giving you room to feed. It’s like the canvass you paint on.
Watch for sodium buildup. Na/K over 10% of your base will block P.
I usually have plenty Ca from my water and amendments. I'd say most of my soil has high Ca. The flowering plant that's showing Mg deficiency is probably due to the higher Ca levels. That's why the extra langbeinite works so well for me. I just ran out of my second 5 lb box today. This time I'm going down the road to Grow Generation to get a 50lb bag for $60. I think I've been paying like $20 for 5 lbs.
The langbeinite helps with Na buildup too.
The 120 calcium carbonate on the test doesn’t mean actual ca ppm. It is a calcium carbonate equivalent. A good water test will help your grow. Should see swollen internodes with good calcium. How stable is ph in your 15’s?
I know the carbonate is pretty inaccessible Ca but my big pots have plenty Ca so I assume the 5 gal would too. Don't you usually see the brown spots with Ca deficiency though? The pH is super stable in the 15's.
Calcium deficiency can show up looking like many things. Calcium is also easily blocked compared to p.
Btw. Five years in same mix is good work.
Calcium deficiency couldn't cause that edges yellowing could it?
I figured more of a ph shift caused that. I suspect high sodium causing p/k problems for you.
So are you saying sodium can lockout potassium? Actually that makes sense.
Absolutely. And combined na/k can lockout p. It’s difficult to keep the sodium down and with the peat moss additions aluminum(blocks p)also becomes a factor too. You have good amounts of feed after five years but it’s out of balance. If you take the time to test you’ll save money on inputs and have a healthier grow. Balanced minerals the best you can plus push biology ftw.
I know people always say don't water organics to runoff but I always water until a little water comes out the bottom. My thought is it flushes out a tiny bit each time so stuff like Na doesn't build up.
With the inputs you listed your bound to get sodium buildup. It will have you chasing your tail too.
The only input that I know of that has high sodium is the kelp. What else are you thinking?
