Large ridges between veins on new growth and lots of curled leaf fringes – See bottom right pic here:
Few days later, upper leave stems showing a bit of purple. Taco’d leaves unchanged. Upper part of plant remains kind of olive. New growth appears succulent, less pronounced ridges, reduced leaf size and narrow, reduced vigor in upper growth. Lower growth remains lush and healthy.
Theory is that with hi temps, this one started to dry up, drank up most of the water in the soil. EC went up from the calmag salts, and with less water in the soil, salt concentration went too high.
Looking for input on best way to facilitate recovery from heat stress and salts.
Seemed to even be some white salt deposits on some upper leaves.
Seems unlikely to be Mg related with this high of calmag. Prior to arriving at the above now apparently obvious theory, tried a small spot foliar treatment of Mg just to be sure – no affect. Tried some spot foliar treatments of micros, mild tiger bloom, kelp. No affect. Large plant, easy to do a few spot treatments and not affect the whole thing.
Would like to do all possible to facility quick and full recovery.
Lots of kelp? Water/foliar?
Would aspirin / salicylic acid be worth while? What recipe and best way to apply?
Looking for input on best way to facilitate recovery from heat stress and salts. Large greenhouse plant (green crack), in well amended soil/coco/perlite…
Heat during the flowering stage also causes fox-tails, which are airy and don’t have much substance to them. It’s basically the same response as growing new buds on top, it just looks a little different on some plants. The plant is basically “abandoning” the original heat-damaged bud to try to make a sad new one.
It is possible to partially shield your plants when you know the temperature is going to get hot. You can also adjust your watering schedule to make sure plants at least have plenty of water.
Even though the grow lights were turned off, this is what happened to an indica-leaning plant overnight after being exposed to 105°F (40°C) temperatures during a heat wave.
Example of unwanted “fox-tailing” caused by too much heat
When the heat gets too high, the edges of the serrated leaves will begin to curl up even if there are no burns or other signs of light stress.
Indoors, find a way to lower the temperature and/or increase the circulation in the grow room or grow area if heat is the problem. Having a small fan blowing over the tops of your plants will help prevent hot spots from forming directly under your grow lights. How far away should you keep your grow lights from your plants?
An oscillating fan will circulate air in the room as well as provide a gentle breeze for your plants, and a small one will cost less than $20.
When the heat gets too high, the edges of the leaves will begin to curl up and the leaves will begin to “cup.”
If flowering cannabis plants are grown under too-hot conditions for a long time, sometimes they respond by growing new buds on top of the old ones. When you see extensive growth on top of the buds closest to the grow lights, that’s a sign that the grow light is too close or the temperature is too high. Some people call the new growth (which often grows in spires) “fox tails.”
Too hot for your cannabis in the grow room? Learn how to save your plants from heat stress with a variety of techniques as well as certain supplements!