Excess growth can be slowed by growing crops cooler with increased spacing and using less water, a term called growing “harder.” If space allows, increase plant spacing and if crops can take colder temperatures in the 60º F range, you may want to consider this approach.
What slows down vegetative growth? If the balance tips to generative growth, more energy, water and nutrients are directed to the growth of the generative parts and vegetative growth is slowed down.
As stated, the longer you veg the plant, the taller it will grow. So switch it at the right time. If it does get too big, top it, let it recover, and then switch it to flowering. You have a lot of room to play around while you're still in the vegetative stage.
A plant can be maintained in vegetative growth without being allowed to flower indefinitely with no adverse effects. Typically indoor growers who can control their light cycles will use either 18 hours of light per day or 24 hours of light per day.
In vegetative growth, ethylene appears to have a dual role, stimulating and inhibiting growth, depending on the species, tissue, and cell type, developmental stage, hormonal status, and environmental conditions.
Vegetative Stage: As the third stage of cannabis growth, the vegetative phase usually takes two to eight weeks, but it can last as long as 16 weeks. In the vegetative stage, weed plants grow at a fast rate with additional nutrients and carbon dioxide.
Nitrogen is the most important nutrient to have abundantly available to your plants during the vegetative stage, as this nutrient is the staple component for vigorous root, stalk, stem, and leaf growth.
You should use 5 ml/gallon of Cal-Mag Plus during the vegetative and early bloom stages. During the halfway point of the flowering stage, you might want to reduce the application to 3 ml/gallon, to avoid adding excess nitrogen to the nutrient solution based upon your plant specific needs.
A good potting mix that is well-fortified with organic materials and perhaps even some mineral fertilizer will require less feeding than a medium that is more inert such as rockwool. For a standard potting mix, fertilizing once or twice a week should be sufficient.
You can remove fan leaves during flowering in much the same way you do during veg. Prune away large leaves that are overshadowing bud sites, as well as dead or dying fan leaves. One thing to keep in mind is that you should prune in intervals, giving at least a couple weeks between each session.
The best way to solve the problem of over-fertilization is to leach excess nutrients from the soil by using watering to slowly flush out the pot. (Your pot will need drainage holes for this.) To leach the soil, put your plant in a sink, tub, or outside where it can drain and give it a nice, long watering.
Physical control options include container size, timing, water stress, nutrient stress, mechanical conditioning, spacing, light quality and quantity, pinching and temperature. Restricting roots can also control plant growth. This is done by using a smaller container or a higher number of plants per pot.
Old, dirty greenhouse film in combination with lack of daytime ventilation commonly causes plant stretch. Depending on the extent of these factors, growers can sometimes use cultural practices and plant growth regulators to salvage plants by slowing down stretch.
Install root barriers before the roots reach the concrete. Cut the roots and dam them with root barriers to prevent further growth. Cut down the tree and remove the root system so you can make a smooth, level surface again.
The longer you keep your plants in the vegetative stage, the bigger your plant will be, resulting in bigger yields from plants that were vegetated longer.
Topping should be done when the plant is still in its vegetative stage and just starting to grow buds. It's essential to be aware of the effects of topping on the plant and its yield, as it can have a huge impact on the quality of your final product.
Vegetative
Lasting between 3 to 16 weeks, the vegetative stage requires full-spectrum light for 18 hours and 6 hours of darkness. Some argue for 24-hour light cycles during this stage, but that choice may lead to nutritional deficiencies and stunted growth in the final flowering stage.
Excessive calcium can interfere with uptake of other nutrients and induce deficiencies in other positively charged ions (e.g., ammonium, magnesium, potassium). Symptoms appear first on older leaves as yellowing between leaf veins, and in severe cases can be followed by death of these areas and defoliation (Fig. 262).
Vegetable Gardens & Epsom Salt
Ultra Epsom Salt does not accumulate in the soil or harm any plants when used, so it can be used safely and effectively during any stage of the plant's life. For general purposes, Ultra Epsom Salt works well as a saline solution for a tank sprayer.
DOSE OF CALCIUM AND MAGNESIUM IN PLANTS
However, added high doses of calcium and magnesium supplements can cause deficiencies too in our plants, like limescale in the root stem, damaging roots and avoiding the plant capacity to absorb necessary nutrients.
For soil growers, plants can be fed once every second or third watering. If plants are fed with every watering then nutrient buildup and lockup becomes a problem causing stunted growth, “crows foot” (curling downwards of the leaves), leaf burn, deficiency symptoms, burnt and damaged root system and decreased yields.
During the vegetative stage, a Cannabis plant growing indoors needs 18 hours of light and 6 hours of darkness a day. The vegetative stage may last for as long as you want in indoor crops. Your plant will continue to grow in size and won't flower until you change the photoperiod.
It depends on the stage of growth! For lush, bushy foliage in the vegetative stage, we recommend a potassium heavy 8-4-13. For big, dense, sticky buds in the flowering stage, more phosphorus and less nitrogen is needed in a 5-10-14 formula.