This is a mistake that most novices make. They add too much fertilizer to their plants or choose the wrong nutrient ratio in different growth periods. For specific fertilizer addition methods, please refer to Weed Grow Lesson 19: How to choose a suitable fertilizer for cannabis?.
Here, we must first distinguish the concept of nutrition for all growers. Water, nutrition, and air are the living environment of cannabis, and light is the food of cannabis. Many cannabis growers mistakenly believe that strong nutrition will make cannabis grow faster. This idea is wrong. Adequate nutrition can satisfy the growth potential of cannabis. It is light that gives the marijuana the growth rate, and the nutrition is only provided by the light to grow.
Different degrees of overnutrition symptoms of cannabis
A slight overnutrition will not harm the cannabis, it looks like overwatering. Unless a soil moisture meter is used, it is difficult to distinguish.
A moderate overnutrition will make the tips of the cannabis leaves turn yellow and withered.
Severe overnutrition will cause large areas of leaf tips to turn yellow and wither.
Excess nutrients on new leaves will also show leaf tip curling.
The burning caused by overnutrition is similar to the severe yellowing caused by overwatering. The first cause of overnutrition is the withering of the leaf tips, and the withering caused by excessive watering is the withering of the leaf periphery or leaf surface.
After the marijuana enters the flowering period, the plant is less likely to replace the injured and dead leaves. When the cannabis matures, the plant will give up repairing the damage to the leaves and will focus all its energy on germination. Therefore, severe nutrient burning is fatal during the flowering period.
The flower buds of cannabis require more potassium and more phosphorus. The nutrients that can satisfy the complete development of the flower buds are excessive for the leaves, which will cause slight burning. In order to satisfy the development of flower buds, these slight burns can be ignored.
It often causes nutrient burn in hydroponics, and many growers are too greedy for growth speed or use the wrong ratio. I suggest that hydroponic growers can choose a nutrient solution suitable for tomatoes and dilute it to about 75% of the stated concentration. As long as the nutrient ratio is right, a small amount is better than an excessive amount.
It should be noted that whether it is hydroponics or soil culture, before judging whether there is excess or nutrient deficiency, a PH test must be done first, and indeed the pH is suitable. There is a difference between the yellowing of the leaf surface caused by the fluctuation or unsuitability of PH and the yellowing of the leaf surface caused by nutrient burning, and the influence of unsuitable PH on the leaf tip is not different.
Most of the mild nutritional burns can be ignored, as long as the air humidity is 40%, the temperature is 20-28 degrees Celsius, and the light intensity is 10,000 to 30,000 low pressure environment to let it recover slowly.
For severe nutrient burning, first determine whether the pH is appropriate, and if appropriate, start to rinse the plants. For details, see Weed Grow Lesson 5: First aid! How to rinse cannabis plants after over-fertilization.
Fertilization and watering are common mistakes made by novices. Don’t be too greedy for growth speed when you first plant. Give a comfortable growth environment to let the hemp grow first, and then consider the yield of flower buds. Whether it is fertilization or watering, it should be slow Slowly, start with a small amount, especially fertilizing.