Dry crispy set of true leaves

Ahoy there @whig217 ! I just stumbled in here on accident as I generally only read threads As to your plant problem. Many things can cause a leaf to burn, too much of something is usually the cause. How is the new growth on the plant looking?

If you are asking about watering perhaps we should cover the basics about watering and fertigating.
Here are the basic rules: Never let the soil dry out. Soil and or coco can become hydrophobic if allowed to dry. This means it repels water. This in turn will create dry pockets in the soil and the roots and microbes will die there. If your soil - coco have accidentally dried out use a surfactant to help re-wet it. I like yucca powder. Don't let soil remain soggy by watering too much too often. Root rot, damping off, molds, fungus gnats and other problems start in soggy soil. When you do water water the entire pot. How to learn when to water starts before you plant the seed. Fill your container with fresh soil/coco and weigh it (heft it) this is the lightest weight and consider it a dry pot. Now slowly water until the soil/coco will no longer absorb the water and run-off begins; weigh the pot (heft it) this is the maximum water, the wettest the pot can get. The difference between wettest and driest is the maximum water weight, for ease of explanation lets just say the water weighs 20 pounds. When the pot loses 10 pounds (half of the water weight) it is time to water again. Slowly wet ALL of the soil until run-off begins. There is an art to watering. Make sure there is an air gap under your pot, you do not want runoff to be reabsorbed and if no air then anaerobic microbes can grow. This is a cause of root rot. Coco can be fertigate many times a day if you want to continually present fresh balanced nutrients to the roots. Begin fertigation 2 hours after lights on and end it 2 hours before lights out.



Now for coco. Coco is a form of Hydroponics and you water with nutrients every time you water. It is called fertigation when nutrients are mixed in the water. The idea behind coco is a substrate that you cannot over-water. It simply drains out the bottom pulling air into the roots. This allows you to fertigate several times a day presenting fresh in balance nutrients to the roots all day. Do not fertigate sooner than two hours after lights on or after two hours before lights out. During the night the roots will be exuding substances to feed the microbes so they will produce more nutrients the plant is look for. If you fertigate too soon after the lights come on the plant will not have a chance to take in the nutrients the microbes made before you wash them out. Then at night the plants do not like to go to bed with wet feet . Just because it is hydro does not mean it does not have a rhizosphere it does. Always fertigate to 15% run-off every day in coco. Don't let the pot sit in that drainage remove it to waste (feed your outdoor plants with it).


A tap root can grow 9 inches in three days and the laterals are not far behind. Roots will not grow into dry soil. This is the mechanism behind air pruning. So if you have a dry pot you will stunt the root growth at the time when it is most crucial. Water/fertigate the entire pot when it is needed.