Once a root system has developed, you can switch to watering routines that will see you all the way through to harvest. In line with the guidance above, watering should take place every 2–3 days, or when the surrounding soil is dry to the touch. The most effective way to get into good habits with watering is to water at the start of the day. For outdoor cultivations, plants will have an entire day of sunlight to utilise. If growing indoors, it is helpful to set your grow lights to come on at the start of the day, just as you are watering.
Consistency in watering routines supports another vital building block of cannabis—nutrition. Your plant’s root system will absorb essential nutrients from its growing medium, but only when pH levels are optimal (6.0–7.0 pH for soil, 5.5–6.5 for hydro/soilless/coco). The key is to keep plants watered on a schedule. Not only does it keep plants routinely hydrated, but it will prevent fluctuations in pH—a symptom diagnosed by brown spots on middle or lower leaves.
Even if you know how to manage water-related issues, you still need to establish the best time to water cannabis plants. Timing goes hand in hand with the techniques listed above, varying according to the seedling, vegetative, and flowering stages.
To maximise nutrient uptake, aim for 10–20% runoff every time you water. Adopting this approach at an early stage should keep pH fluctuations to a minimum. However, it is especially vital if you are increasing nutrient concentrations for any reason (bloom boosters during flowering, for example).
It’s possible to get your plant back on track after a period of underwatering, depending on the severity of the situation. If your plant has been significantly neglected and is literally lying on the topsoil, then the chances are low. However, if all you’re seeing is slight drooping of the leaves and general wilting, all it takes is readjusting your watering schedule.
One key piece of cannabis anatomy is the root system. As well as anchoring plants securely into the soil to prevent the wind from blowing them over, the roots act to absorb water and nutrients from the soil below. A little-known fact is that plants also use their roots to take in oxygen. If you give your plants too much water, or the correct amount, but too often, you obstruct their ability to intake oxygen, which then results in symptoms arising.
Overwatering cannabis plants is a very common mistake in novice growers. It’s usually the result of caring slightly too much and providing an excess of a key resource. For some growers, the sight of slight dryness in the topsoil is enough to induce panic. It looks as though their plant is about to dry out and die, so they proceed by drenching the soil with too much water, too frequently.
Watering in the evening is an option, but the lower evening and nighttime temperatures can lead to a buildup of mould.
Underwatering can occur due to a busy schedule that forces a cultivator to forget, or it can arise in areas of high heat where watering is required more often. Underwatered plants will also appear to have an ill and weak look to them. Their leaves will be dry and droopy, and the tip of the plant may be bent into one direction.
Underwatering and overwatering produce similar symptoms and are both detrimental to plants. Learn how to manage watering correctly to avoid these issues.
With the above in mind, you should be well on your way to understanding how over and underwatering affects your plants – as well as overall water quality in general.
Cannabis plants consist of approximately 90% water, and the substance is required during various vital physiological process such as photosynthesis and transpiration. When using a poor quality water source to supply cannabis plants, these processes may be less efficient than they can be, or in worst case scenarios, disruptive.
As well as watering frequency, the quality of the water used to supply a cannabis crop is also a highly important consideration.
Overwatering and under watering your cannabis plants can cause multiple symptoms and may even slow down growth. It’s all about understanding your plants and finding a sweet spot. We explore how to recognize and fix these issues, as well as take a look at the importance of water quality in general.
1. One primary symptom of overwatering is drooping leaves. However, it is not the same kind of droop you see when underwatered – where leaves look wilted. It is the opposite in fact. Leaves are so full of water, that they are being forced to curl in on themselves. It results in them becoming very firm.
Before the growing process, check the quality of your water source. One important factor when it comes to water quality is pH. pH is a numeric scale used to measure the acidity or alkalinity of a solution, with the middle value of 7 representing neutral. Numbers less than 7 represent acidity and numbers above 7 display alkalinity.
When these disruptions occur, symptoms may manifest that appear almost identical to an array of other conditions such as over or under fertilisation, under-watering, and possibly even heat stress. This is a perfect example of why to always double and triple check the root cause of the problem when troubleshooting health issue of cannabis plants.
Overwatering is an easy mistake to make when growing cannabis, and is most likely caused by worrying that plants need constant doses of water. It is a pitfall novice often fall into.
1. Underwatered cannabis plants will look very weak, lifeless, and will show signs of wilting. Its no wonder they begin to look this way considering the vital role of water in plant physiology. The wilting of underwatered cannabis is different from the plump curling of overwatering – even if only subtly. Leaves will be fragile, brittle and even papery. They will look lifeless and drab. Another sign of an under watered cannabis plant an extremely dry growing medium, such as crispy soil.
We explore how to recognise and fix cannabis over and underwatering, as well as the importance of good quality water.