phxazcraig
- 543
- 93
I'm trying to recognize a problem in the early stages and head it off. In the past couple of days I've noticed a few leaves starting to curl at the edges, particularly on one leaf on the plant closest to a rotating fan. (Wind damage in part?) I have two other plants (of 4) with very preliminary signs, or whole leaves twisting sideways a bit.
I'm trying to find all probable causes for leaf edge curling. My guess at this point is heat stress. Here are answers to the questions in the Read Me First post.
Hydro Growers:
(I'm going in a prepared coco coir mix from Roots Organics.)
1. Are you growing from seed or clones?
seed
2. How old are your plants?
seeds sprouted Jan 7 into Jiffy pots which immediately went into solo cups. Transplanted to 3.5 gallon air pots at about 8-10 days after sprouting.
3. How tall are your plants?
6-7 inches, but they've been topped a few days ago at the 5th node.
4. What type of hydro system are you using?
DTW, homemade.
5. What brand/type of nutrients are you using?
Silicone (then 1 hr delay), Cal/mag, then FF Big Bloom and Grow Big (hydro version), then humic acic (Diamond Nectar) and a bit of Yucca powder.
6. What is the Ph of your nutrient solution?
6.0. Controlled via pH Down and a Bluelab controller
7. What is the PPM/EC of your tap water?
It's very high (513/1087 - Phoenix AZ has very hard water)
8. What is the PPM/EC of your nutrient solution?
The current batch is 870/1853. The EC is a bit higher than desired here.
Runoff from this morning's watering was 814ppm and 1.717 EC. In the past the PPM went up a bit, and EC tended to go up by about 0.300. I'm still dialing in the amount of water to fertigate, but I'm guessing about a gallon for each watering split between 4 plants. I get a bit under a gallon runoff. I run the reservoir pump for 30 seconds at 6am when lights come on and 4:30pm. The lights go out at midnight for an 18/6 schedule.
9. What is the temperature of your nutrient solution?
75F
10. Does your PPM/EC show a rise or fall when you do your daily PPM check?
pH is tightly controlled by the Bluelab controller, so it stays right at 6.0 where I set it. I have not checked EC daily, but I don't think it is changing.
11. Does your pH show a rise or fall when you do your daily check?
Stable
12. Do you foliar feed or spray your plants with anything?
None
13. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights")
I use a 600w HLG 600r.
14. How close are your lights to the plants?
Varies, but about 2 feet for now. I am limited on height of the tent, so I make do by controlling power via dimmer and measure with PAR meter. Currently running about 450 PAR at the tops of the plants.
15. What size is your grow space in square feet?
4x4
16. What is the temperature and humidity in your grow space?
Temps range from 77 at night to 84F during most of the day when the light is on. 6-inch duct fan comes on at 80F and off at 77F. RH usually around 40-45% during day, up to 75 at night when fan finally shuts off. Being in Phoenix I have very little control over humidity, some over temps. There is a humidifier in the tent, and the room door is usually closed. (Closed during winter. Too hot in summer to do that, so even less humidity control then.
17. Have you noticed any insect activity in your grow space?
None
18. How much experience do you have growing?
This is my third crop over past year, first in Coco.
I'm trying to find all probable causes for leaf edge curling. My guess at this point is heat stress. Here are answers to the questions in the Read Me First post.
Hydro Growers:
(I'm going in a prepared coco coir mix from Roots Organics.)
1. Are you growing from seed or clones?
seed
2. How old are your plants?
seeds sprouted Jan 7 into Jiffy pots which immediately went into solo cups. Transplanted to 3.5 gallon air pots at about 8-10 days after sprouting.
3. How tall are your plants?
6-7 inches, but they've been topped a few days ago at the 5th node.
4. What type of hydro system are you using?
DTW, homemade.
5. What brand/type of nutrients are you using?
Silicone (then 1 hr delay), Cal/mag, then FF Big Bloom and Grow Big (hydro version), then humic acic (Diamond Nectar) and a bit of Yucca powder.
6. What is the Ph of your nutrient solution?
6.0. Controlled via pH Down and a Bluelab controller
7. What is the PPM/EC of your tap water?
It's very high (513/1087 - Phoenix AZ has very hard water)
8. What is the PPM/EC of your nutrient solution?
The current batch is 870/1853. The EC is a bit higher than desired here.
Runoff from this morning's watering was 814ppm and 1.717 EC. In the past the PPM went up a bit, and EC tended to go up by about 0.300. I'm still dialing in the amount of water to fertigate, but I'm guessing about a gallon for each watering split between 4 plants. I get a bit under a gallon runoff. I run the reservoir pump for 30 seconds at 6am when lights come on and 4:30pm. The lights go out at midnight for an 18/6 schedule.
9. What is the temperature of your nutrient solution?
75F
10. Does your PPM/EC show a rise or fall when you do your daily PPM check?
pH is tightly controlled by the Bluelab controller, so it stays right at 6.0 where I set it. I have not checked EC daily, but I don't think it is changing.
11. Does your pH show a rise or fall when you do your daily check?
Stable
12. Do you foliar feed or spray your plants with anything?
None
13. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights")
I use a 600w HLG 600r.
14. How close are your lights to the plants?
Varies, but about 2 feet for now. I am limited on height of the tent, so I make do by controlling power via dimmer and measure with PAR meter. Currently running about 450 PAR at the tops of the plants.
15. What size is your grow space in square feet?
4x4
16. What is the temperature and humidity in your grow space?
Temps range from 77 at night to 84F during most of the day when the light is on. 6-inch duct fan comes on at 80F and off at 77F. RH usually around 40-45% during day, up to 75 at night when fan finally shuts off. Being in Phoenix I have very little control over humidity, some over temps. There is a humidifier in the tent, and the room door is usually closed. (Closed during winter. Too hot in summer to do that, so even less humidity control then.
17. Have you noticed any insect activity in your grow space?
None
18. How much experience do you have growing?
This is my third crop over past year, first in Coco.