Would like to do all possible to facility quick and full recovery.
This one the upper leaves taco’d up, lost most of their sheen, turned an olive type color. Lower leaves and tops shaded by the rest of the plant unaffected and lush. No wilting.
Looking for input on best way to facilitate recovery from heat stress and salts.
Misters cool the greenhouse, failed one afternoon, temps 100+.
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.
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.
Foliared Thrive Alive. Flushed with some straight RO, watering with reduced 100ppm calmag to reduce salt buildup. Working to keep roots from becoming waterlogged (drinks much less). Fixed mister problem.
Would aspirin / salicylic acid be worth while? What recipe and best way to apply?
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.
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…
If you run CO2 your can run a bit warmer than without. If you are struggling with heat and all of your other factors are ideal make sure you have enough carbon dioxide to allow you to run a bit warmer. If you are running double- ended HID lamps that generate more radiant heat of the leaf surface run your temperature at around 80 degrees and no closer that 36 inches from the top of the plant canopy, If running LED lights temperatures can be raised slightly to 85 degrees as they offer less radiant heat on the leaf surface. LED fixtures can be placed closer to the plants as well at 24 inches. Heat plays a huge role in your growing decisions and your light choice mirrors that importance. The above temperature suggestions are with CO2 if you don’t have high levels back off by 5 degrees on each light source.
When Cannabis is too cold growth can slow or stop completely, often when dark cycle temperatures drop below 10 degrees Fahrenheit compared to light on temperatures growth is stalled until temperatures climb within the proper range for plant processes to start again essentially remaining dormant; example lights on 85 degrees and lights off 75 degrees. If you are too hot during your lights on stage you may see signs of having heat stress: If you start to notice curling leaf tips or the entire leaf starting to curl up or taco without the noticeable burnt tips often associated with nutrient burn you may be experiencing heat stress.
Problem: All plant require heat to live and grow, your cannabis plants, although it grows like a weed, can only take so much. Too much heat often coupled with other variables will have your plants stressed out and if it is prolonged stress will start to negatively impact your yield and your quality. But how much is too little or too much?
Firstly, you need good air movement within your growing environment, there should be a gentle breeze moving each and every leaf within the room breaking up the stratified stale air moving the hot humid air away from the leaf surface replaced with cooler dryer air enriched with CO2. Important to note is that you want a gentle breeze not a windstorm causing wind burn. On the topic of humidity consult a VPD chart or vapor pressure deficit chart that will illustrate the ideal temperature to humidity ratio according to each stage of plant growth and development.
Temperature is a critical component of any growing environment and ties in directly with humidity. If temperatures are too high and humidity is low then signs can quickly develop of heat stress whereas high temperatures and high humidity can lead to disease and mold including bud rot. Knowing your temperature and humidity is key, having quality monitors displaying high and lows is essential. Some things to consider when growing cannabis indoors under lights is proper grow room environments.
Secondly, ventilation by way of fresh air or by air conditioning will bring your temps into the proper range. In the event that you can’t cool your space with using fresh air make sure to run your lights as much as you can during the nighttime when outside temperatures are naturally cooler.
Fourthly, keep your plants well watered-dry roots and high temperatures equals death. Keep plants well watered with slightly weaker nutrients to help them overcome the stress. If growing in above ground containers covering then with reflective material or paint will help reflect some of the radiant heat from the lights or sun as long as it doesn’t impair drainage. If in hydroponics or recirculating systems try and maintain reservoir temperatures of 67-70 degrees.
Thirdly, choose your lights carefully, if you are using LED lights you can run slightly warmer temperature because the lights don’t generate as much radiant heat on the leaf surface whereas HID lights such as double-ended HPS lamps need to run at slightly cooler temperatures as they create more radiant heat of the leaf surface.
Heat Stress Heat Stress Problem: All plant require heat to live and grow, your cannabis plants, although it grows like a weed, can only take so much. Too much heat often coupled with other