Indica leaves are short and wide, typically with 7-9 fat fingers. The heaviest indicas of Afghan origin can have oversized, extra-wide fan leaves. Indica leaves are a darker, deeper shade of green. The higher chlorophyll content is believed to accelerate the bloom cycle of indica varieties.
Fan leaves have very low cannabinoid content and are best added to the compost heap for next season’s super soil mix. Sugar leaves, or the resinous trim leaf that a grower accumulates during the harvest process, is excellent raw material for homemade cannabis concentrates.
Yellow leaves are a warning sign and a cry for help from the cannabis plant. Unfortunately, many nutrient deficiencies, over-fertilisation, and heat stress can cause leaves to yellow and wither. It’s so important to closely monitor your cannabis crop, be it indoors or outdoors. If you have been paying attention, you can take corrective action with more confidence diagnosing.
An eyeball inspection might be insufficient to accurately diagnose a possible pest infestation. Discolouration of leaves is not enough evidence to jump to conclusions. However, a thorough eyeball inspection will reveal some pests’ presence. Leaf miners will leave telltale tunnels as they eat their way through leaves. If you see white veins running through leaves, it’s time to get some neem oil.
Fluctuations in pH are responsible for the majority of yellow leaves. When the water pH is outside of the optimal ranges for your growing medium, the roots cannot access all the nutrients they need. Nutrient lockout is perhaps the most common cause of yellow leaves in cannabis plants.
Every cannabis cultivator needs to be able to interpret the signals weed leaves send. The grower that can read cannabis leaves correctly will crop healthy plants with fantastic buds. Here is your go-to overview of the weed leaf.
A visual inspection using a pocket microscope will reveal the presence of other microbial nasties. Be on the lookout for eggs, larvae, fungal spores, and mould. Leaf septoria is caused by the fungus Septoria lycopersici. This particular invader is often misdiagnosed as one of many possible nutrient deficiencies. Yellow spots suddenly presenting on leaves early in flowering, followed by a rapid yellowing and browning of foliage can destroy the whole crop rapidly. There is no time to waste with misdiagnosis.
Weed leaves are key components of the cannabis plant’s life support system. The green pigment chlorophyll allows leaves to act as solar panels for marijuana. Leaves are essential to photosynthesis. Moreover, the underside of leaves are covered in tiny stomata. These microscopic holes open and close like a door. Carbon dioxide goes in, oxygen and water goes out. Furthermore, leaves can also absorb nutrients to feed the cannabis plant, this is known as foliar feeding.
Three kinds of cannabis species are generally agreed upon. Although all three are often lumped together under the official classification of Cannabis sativa L., for practical purposes, it helps to make distinctions between sativa, indica, and ruderalis. That being said, most cannabis you encounter these days is a hybrid. Thus, what you will typically see in the grow-op are weed leaves that express a blend of genetic traits.
Marijuana is coveted for her resinous flowers. It’s about time the humble weed leaf got some recognition. Let’s discuss the importance of cannabis leaves.
The leaves of cannabis plants can be very telling. Here are some tell-tale signs of a mishap in the making that can be seen by merely inspecting the leaves:
C. sativa leaves are long and slender, often with pronounced serrations, giving the leaves a jagged, almost spiky appearance. The colour of sativa leaves ranges from bright, lime green to blackish-green at the darkest. The largest leaves can often have up to thirteen leaflets.
Whorled phyllotaxy is another common mutation, although this is less desirable as a concealment trait as the plants still definitely resemble cannabis.
The leaves of a cannabis plant play a big role in supporting its growth and the overall health of the plant. The stomata on the bottom of the leaves, which are tiny little holes that open and close, take in carbon dioxide and release water and oxygen. This is required for photosynthesis, which would be near impossible without the leaves. They also provide a way for the plant to absorb nutrients (foliar feeding).
C. ruderalis leaves are generally smaller than the other subspecies’, as the mature plant is much smaller overall. The largest leaves may contain anything from five to thirteen leaflets. Ruderalis leaves are usually closer to the indica in terms of width, although they can be much narrower than any indica leaf would normally be.
- Blistered, twisted, shiny “wet” looking leaves – This may be an indication of mites, which are too small to see with the naked eye. If this is the case, new leaves may grow in twisted, top leaves can droop.
- Spotted leaves – Spotty leaves may indicate a deficiency (likely a calcium deficiency). This normally affects new leaves or parts that are actively growing.
- Edge of leaves fading to pale yellow – This is likely a sign of magnesium deficiency.
- Edge of leaves change to white or bright yellow – If this is seen along with the inner main part of the leaves turning purplish or dark blue, then there’s probably a copper deficiency. They may also appear shiny or start to turn under. This most often affects leaves directly in the light.
- Curling, folding, miscolouring leaves – If leaves are too close to light or heat, they can start undergoing heat stress. This can lead to them folding up, curling down under and turning yellow or even plainly getting a burnt look to the edges.
- New leaves grow in bright yellow – If new leaves are growing in from the get-go with a bright yellow colour, the plant may have an iron deficiency.
Australian Bastard Cannabis is perhaps the most striking mutation yet seen in cannabis. It is believed that this mutation was first seen in escaped populations around Sydney. Breeders have also attempted to stabilise this trait … again, without commercial success.
This mutation takes the form of hairless, succulent leaflets, usually with no more than five leaflets to a leaf. The individual leaflets usually do not exceed a few centimetres in length.
Although cannabis leaves are usually decussate, as the plant prepares to flower the leaves may begin to emerge in an alternate pattern. Interestingly, rejuvenated cannabis plants demonstrate alternate phyllotaxy.
Cannabis leaves are so recognizable, they’re basically iconic. But what do you know about them? Learn to identify the leaves and what you can do with them.