Hey everyone im new to the site have been reading lots but just registered because im starting to have problems with my first grow. Im growing auto's under a 400w mh and they are just over 2 weeks old. Have a fan blowing around in my grow space which is 3' by 3'. Plants were doing fine until i checked them this morning. Started noticing light green/yellow patches on lower/middle leaves and noticed that the bottom leaves have almost died. Soil im using has a mixture of peat, lime and some organic material and i have added perlite but next to no nutes in the soil, 0.01 pretty much for npk might be a lil higher not much tho. Just starting giving 1/4 dose nutes the other day i believe its 20-30-20(all that i have atm) thinking might be a lil early not sure...The tips of the leaves look fine but it seems like sporadic yellow patches that are progressing..I dont have a ph meter so im thinking it could be ph problems. Let me know what other info you guys need...i appreciate any help that can be forwarded...here's a few pics..
Mix up some Dry Grow Fertilizer with some Peat and top dress your plants grow media. If your growing in a media that has no nutes you need to irrigate a couple times a day to get fresh nutes to all the roots. if you top dress you can water as normal and not risk root rot. and also have the benifit of being able to flush it out when you flower or at harvest. Also the smaller ones are probably ready to transplant I'd give them a dose of a B1 /Growth suppliment with your nutes when you water then transplant after about 4 days . They dont look too bad to me .I just get them some dry powdered grow fertilizer and cut it with some peat to avoid over fertilizing and put about a 1/2 inch of it on the top of your original soil mix and water . They'll love it
Also If you can get some dolomite lime and mix a cup per 5 gallon of your grow media it will stabilize the ph of your grow media because it neutralizes both acids and alkalines to about 6.5 to 7 which is perfect for pot. and its fairly cheap.
Hi thanks for answering....gave them a lil flushing of tap water and it seem to perk em up but still yellowing...not quite yellow but lighter green...so you figure it needs more nutes just top dressed? i was thinking i over fetilized even tho it was 1/4 dose. i was thinking about waiting until i know which were fem before transplanting just cuz of space. The three that are in the big pots are fem seeds so i transplanted early. The others are reg and it day 15 for them. Lighting is a 400w MH. Bought a cheap ph meter which says 6.8 or so. Dont think its very accurate. But the dolomite lime might not hurt either. Plants tho were looking good until 2 days after nutes.