Yellowing tops at end of 4 weeks flower

drkstr67

Active Member
My problem is yellowing tops and on some right down to the buds, I have been feeding with GH 1-2-3 for the last two weeks and am in week four of flower. The damage seems to be occurring under the light and when moved away begins to green up again.
Nutes have been between 1050 ppm and 1400 ppm, PH 5.6 - 5.9. Fresh water add back between nute top ups. I'm in 4" rockwool cubes with 3 floods a night.
View attachment 1210272View attachment 1210273
 

Mazar i Shariff

Active Member
You are slightly Nitrogen defecient. You're probably feeding a lot of bloom boosters that are high in Phosphorus & Potassium but lacking ideal levels of Nitrogen that your plants need to maintain lush, green fan leaves that you'll need atleast til Week 7-8 for photosynthesis/energy for bud development. After Week 7-8, you can sacrifice these leaves by doing a soil/hydro flush with either Water Only or Water & a Chelating/Flushing agent. This will allow you to pull excess salts/nutrients/chlorophyll out of your plant which may have a high concentration of some or all of the above. Removing this excess will enhance aroma, smoke, & flavor.

Hope this helps!

+rep??? :)
 

drkstr67

Active Member
Thanks for the reply Mazar. I was just using straight GH at 1G-2M-3B ratio. No boosters. I ended up bumping up the entire nutrient strength to 1400ppm, drifted down to 1250 over three days, and the problem hasn't gotten worse and is slowly getting a bit better.
 

Serapis

Well-Known Member
You are slightly Nitrogen defecient. You're probably feeding a lot of bloom boosters that are high in Phosphorus & Potassium but lacking ideal levels of Nitrogen that your plants need to maintain lush, green fan leaves that you'll need atleast til Week 7-8 for photosynthesis/energy for bud development. After Week 7-8, you can sacrifice these leaves by doing a soil/hydro flush with either Water Only or Water & a Chelating/Flushing agent. This will allow you to pull excess salts/nutrients/chlorophyll out of your plant which may have a high concentration of some or all of the above. Removing this excess will enhance aroma, smoke, & flavor.

Hope this helps!

+rep??? :)
+REP from me.

I have this exact same problem on 3 of my 5 Bubblelicious plants, that also just finished 4 weeks of flowering. The tops are turning pale yellow to almost white, but rest of plant looks good. My leaves show no damage or curling, just a severe loss of green. I am using flowering boosters and Grow Big was part of my routine for last two weeks.

I just looked it up in the Garden Savers Handbook and it appears to be a lack of Iron.
 

drkstr67

Active Member
What is your ppm at?
+REP from me.

I have this exact same problem on 3 of my 5 Bubblelicious plants, that also just finished 4 weeks of flowering. The tops are turning pale yellow to almost white, but rest of plant looks good. My leaves show no damage or curling, just a severe loss of green. I am using flowering boosters and Grow Big was part of my routine for last two weeks.

I just looked it up in the Garden Savers Handbook and it appears to be a lack of Iron.
 
Top