Unless you are using the hydroponic or aeroponic way of growing, it is simply impossible to know what is going on with the roots of the plants. Watering and feeding cannabis is mostly based on intuition.
Obviously, even if you water your garden without any scheme or rules, the plants will grow anyway. The question is only whether you will like the result: overhydrated plants tend to rot and give little yield (if any), while the plants that experienced too many dry days will provide a small harvest as well. Since all of us want to make our beloved cannabis grow healthy and give abundant buds by the end of the flowering period, it is better to use some of the following tips to make the watering more effective.
Perlite is created from heated obsidian glass. Due to its properties, it can prevent the soil from clumping. It is light and porous, which helps the water and oxygen get to the roots of the plants. You do not need to add much to your soil; just a handful for a usual pot is enough.
If you add perlite to your pot, it would also be wise to apply a drip line. The thing is, perlite is very light, therefore, it can come to the surface of the pot when you water it. A drip line allows you to water the plant all over the space inside the pot. It also helps prevent water from evaporating if you grow your garden outside in the hot climate.
Smart pots are made of fabric. They are thick enough to keep all the soil inside, but at the same time, they are light enough to let the soil (and roots) breathe. This way, the extra humidity can evaporate, and roots can be safe from overheating and boiling during the hot summer days.
If you take a pot that is too big for the plant, the water will remain in the places the roots cannot reach; therefore, the humidity will evaporate too slowly, and the danger of fungus, root rot, or even insects contamination can increase.
If the pot is too small for the plant, there will never be enough water, and you will have to water your cannabis every single day if not twice a day, and the plant will still look dull and unhealthy.
It is recommended to change the pot gradually, starting with 1×1-inch cubes (for seeds and clones), then moving to 4×4-inch pots, 1 gallon, 3 gallons, 5 gallons, and more if the plant requires it.
The best solution for the plant is to let the pot be slightly bigger than the root knot so that it has room to grow but is not big enough to cause problems.
Even if you have dozens of plants and transplantation will take you long, never forget to check every single plant once you have the opportunity to see the roots. It is recommended to treat the roots as carefully as it is possible, but luckily, you do not need to do anything difficult to examine them.
The plant is ready to be transplanted when the roots are visible and cover the whole ball of soil. All roots should be white. If you notice any yellow or brown roots, it is a sign that you water your cannabis too much. If the roots are weak and tend to break, they do not get enough humidity.
The plant's appearance is the best sign for you to know whether you give the right or wrong amount of water. If there is not enough humidity in the soil, the leaves will quickly lose their strength, become dull and dryish. If you overwater your cannabis, the leaf tips will start to curl, and the strength will also leave the plant. Generally, it is better to give less water than too much, as water not only can make the roots rot, it also prevents the access of oxygen to the soil.
To know whether the soil is still wet, use usual wooden toothpicks. Just simply stick one into the soil and see whether it becomes wet or whether any mud particles stick to it. You need to water the plant only if the stick remains completely dry and the soil lets it in and out without making it dirty.
If you are a busy person, it is easy to forget when you watered your plants the last time, which plants were watered and which were not. If you grow different strains or several generations at the same time, the confusion is almost inevitable. That is why it can be handy to place a schedule of watering next to every lot of plants.
Once you are already an experienced grower and know how much water each plant requires, you can prepare ready tables of watering. If you are not sure about the schedule, use a pencil and mark the days for watering for the following two weeks so that you can adjust it anytime. In most cases, watering plants every two or three days is enough. However, if the growing room is very humid, the plants can require watering even every four days.
You can even get a timer so that you can set it to know when it is time to water the plants. If you use an irrigation system, it can also give you a sign when you need to move from one pot to another so that all of them can receive the same amount of water.
And here we came to the point from which we started. Intuition is crucial. You cannot always rely on rules and data with gardening cannabis, sometimes you just need to do what you think is right or what the situation requires. Some strains are picky, while others are easy to grow, and if you experiment with different plants, you need to adapt every time and be flexible about everything, including the watering part. Just take nice care of your ladies, and they will return you the favor!