Do NOT spray your plants after they begin to flower. That is the gigantic disclaimer that I have to throw at my fellow growers before I begin to tell you when, why, and how I foliar spray my cannabis plants.
When I first began growing cannabis, I just watered the plants and called it good. I did not PH the water and I did not trim any of the lower leaves. I just grew pot. It was very awesome that for 16 weeks, I watered a plant and weed grew out of the ends. I had never grown a plant, a vegetable, fruit, or any other vegetative creature, but cannabis just grew.
When I discovered foliar sprays, it was my buddy Brandon that said, “bro, you ever use foliar sprays? My plants are HUGE in veg.” I like big buds and I cannot lie, so I learned about spraying my plants and the ins and outs of feeding through the leaves. I always assumed that when people spritzed their plants with a squirt bottle, they were just being nice. There is a purpose.
Plants, specifically cannabis, feed directly through the root system, pull the water and nutrients up into the stalk and then distribute into the leaves. When I feed my plants, I supplement the water with nutrients. We don’t want to burn our plants so we need to be careful when adding a foliar spray regiment to your current feeding regiment. I plant in soil/coco mix so I water with nutrients one day and then water with plain water for two waterings and then hit them again with nutrients. But aren’t the plants hungry on the other two days?
Note: If you grow in soil, the soil retains nutrients and acts as a buffer for the plants to keep using the nutrients in the soil every watering until they are used up. Coco and Hydro growers need to constantly add nutrients to their water because their mediums do not hold nutrients or PH value.
Since I do not add nutrients to the water for two cycles and cannabis plants are nitrogen mongers during vegetation, I supplement with leaf feedings. Except for the day that I root feed, I will spray down my vegetative plants (including the first 2 weeks of flower) every single day. The growth that you will see by supplementing this way will have your plants looking like the Incredible Hulk: Big, Green, and Mean.
Right Before, or when the lights turn on is the best time to spray your plants. The plants naturally wake up and want to feed. They will drink moisture from the ground, but the leaves will accept the morning dew as a snack. Let’s give these beauties a boost for their morning glory. When I would use HPS lamps, I would only feed just before lights on. The intensity of the HPS can burn through the leaves.
Filtered water or R/O water.
Add a seaweed supplement – we use Agromar Solutions NPKELP (10ml per gallon)
Add a silica supplement – we use General Hydroponics SilicaBoost (5 ml per gallon)
Ph your water to 5.5 – 5.8 – When feeding through the leaves, the water needs to be a little more acidic to help with absorption.
The leaves have pores just like our skin and they can accept nutrients. I try not to use tap water for my foliar spray because of all the other minerals and such that aren’t buffered through the soil or washed out during watering land directly on the leaves. Make sure that when you are spraying your plant, you spray the underside of the leaves and the stems. Since you never want to over water your plant, I use foliar sprays to help feed above ground.
Using foliar sprays regularly can also assist with pest control by knocking pests off the leaves and stems. Plants love the moisture. I will spray my cuttings with straight R/O water all the time. By giving plants moisture through the leaves, they can concentrate on root development instead of feeding the nutrients up to the leaves. Healthy roots mean healthy plants. Don’t forget the DYNOMYCO!
See the whole cultivation series to keep reading and learning.