Whether you’re growing outdoors or in a greenhouse, crop scouting is a necessary part of herb production. It allows you to detect pests, diseases and other problems that may impact the quality of your crop.
Key pests that should be scouted include aphids, fungus gnat and thrips larvae, immature whiteflies and spider mites.
Insect Damage
The best way to determine if a grow is experiencing pest issues is to perform regular crop scouting. This involves using sticky cards and random plant inspections to identify the signs and symptoms of infestation.
When scouting, use a 10 to 20x hand lens or hands-free magnifier (Optivisor(tm)) to identify key pests and their life stages. For example, look for aphids, fungus gnat and thrips larvae, immature whiteflies and spider mites.
Inspect the leaves of your crop to find signs of insect damage such as defoliation or skeletonization. Some insects, such as aphids and fungus gnats, are capable of doing substantial damage when they feed on leaves.
Chewing insects are another source of plant injury. These insects feed on the foliage of hemp and leave a sticky substance behind that can be damaging to your plant.
These insects can also pierce plants and cause damage through their piercing mouthparts. This type of damage is the most difficult to spot and often goes unnoticed until the pest injects a poison that kills the plant tissue.
A scouting program is a good way to monitor a cannabis grow and prevent problems from developing. In order to minimize damage, be sure to inspect your plants regularly and scout areas that have a high production value, such as flower and fruit buds, and the upper and lower canopy.
During routine scouting, you should also look for the signs of disease such as powdery mildew on mint, rosemary and sage. This disease can overwinter on certain weeds and spores will develop on older leaves, so it’s important to scout susceptible crops weekly.
If powdery mildew is spotted, spray the affected plants with appropriate biofungicides or fungicides and eradicants. This will reduce the likelihood of this fungus spreading to other parts of your crop. A hand lens can help you distinguish the fungus from the whitish-spray residue that is commonly found on leaves.
Insects with Chewing Mouthparts
Among the most common pests that can impact cannabis growers are bugs with chewing mouthparts. These insects can cause damage by feeding on the foliage and flowers of marijuana plants.
Chewing insects can be especially troublesome as they can destroy entire plant parts and prevent you from growing healthy cannabis crops. If you see a leaf that has been defoliated by one of these bugs, it is important to remove the damaged part as soon as possible.
Another common pest that affects marijuana grows is powdery mildew. This fungal disease is easily mistaken for other diseases, so it’s important to scout your grow weekly for signs of this infestation.
Scouting a marijuana crop for powdery mildew requires close inspection of both the upper and lower surfaces of leaves. Look for the white fungal threads that radiate from a central point and chains of powdery mildew spores. These are the telltale signs that you need to inspect the plant for powdery mildew before the disease progresses and causes significant crop damage.
Aphids are small, soft-bodied bugs that feed on the underside of marijuana leaves and stems, draining your weed plant’s nutrients. These pests are yellow, green, brown, white, or black in color and can hide under new growth. They tend to live in colonies under the leaves and stems of your cannabis plants.
Infested aphids will secrete a liquid called honeydew that attracts ants. To get rid of these aphids, cut off any older leaves that are heavily infested and spray them with neem oil or insecticidal soap to remove the pests for good.
Predatory mites can be a problem for marijuana growers as they eat a variety of plants and seeds, including cannabis. These mites are so tiny that they are often hard to spot with the naked eye. Infested plants show signs of distress, such as blistered and twisted leaves that appear plastic-like.
The only way to remove these pests is to apply a chemical spray to the infested plant or soil. To do this, you’ll need a pressure sprayer with insecticidal soap or a mixture of neem oil.
Diseases
When growing a crop, there are many factors that can contribute to disease or pest issues. These can include environmental factors like weather, or abiotic factors such as soil compaction, nutrient deficiencies or herbicide carryover.
Once the cause of a problem is identified, growers can take action to correct it. This can be in the form of nutrient additions, fertilizer management or a change in crop rotation.
A good scout knows how to identify the signs and symptoms of different pests and diseases so that they can take preventative measures before problems escalate. They can also provide valuable data about the status of crops, their growth and development so that the grower can make informed decisions about their operations and what needs to be done next.
The key to successful scouting is to find a person that is motivated, meticulous and pays attention to detail. This person will need an intimate understanding of the crop and environment they will be scouting as well as an ability to keep detailed records.
Scouting is a vital part of any horticultural operation, and is usually performed either internally by the grower or by an outside agency. An internal scout is generally already familiar with the greenhouse or nursery and how it operates. This can help prevent cross-contamination of pathogens and pests from other greenhouses or nurseries.
To scout properly, start by dividing the greenhouse into areas and spending a predetermined amount of time in each area. This will allow you to quickly evaluate overall color, height and uniformity of each plant. If any plants stand out or are a particular concern, spend more time in that area.
Once this overall evaluation is complete, select a random sample of plants for further inspection. Use a hand lens or a microscope to look closely at leaves, stems and flowers for any signs of pests and disease.
It is essential to scout regularly, especially during the critical seedling and growth stages of a cannabis grow, because the early detection of pests can significantly reduce losses. This can mean less time, money and energy spent on pest control programs that don’t work as expected.
Pests
Crop scouting is the process of checking crops on a regular basis to help identify issues that may affect your grow. Issues can range from pests, diseases, weeds or weather risks and can make a big difference to your yields.
The aim of scouting is to determine what pests are present, which ones are harmful and assess how many are damaging the crop. This can help you decide when to apply a control measure and how much of your crop is affected.
Scouting also helps to identify any hot spots in the distribution of a pest, so you can take measures to avoid or reduce problems. It can also help you decide which pesticides or biological controls to use in the future.
You can scout at any stage of your crop’s development. However, it’s a good idea to scout before the start of the growing season, when the plants are small. This will allow you to find any issues early, so you can address them before they become a major problem and reduce the amount of work you have to do later on.
When scouting for insects, you will want to inspect the foliage and flowers of your crop. Look for insect damage to the leaves, flower buds and seed heads. You can also swish a sweep net over the crop to capture insects and count them, using a numeric assessment of pest pressure (per square metre) when needed.
Slugs are another common pest that can cause a lot of damage to your cannabis crop. Look for holes in leaves or stems and shiny mucous-like slime trails.
If you notice any of these, you should scout your grow again as soon as possible to see if the problem has resolved itself. This can help you to make sure that your plants are safe to grow and that they are getting the right amount of light.
If a plant is not healthy, it will not produce as many leaves and flower buds as it should, reducing its yield and producing less cannabis. This can lead to lower prices and a loss of revenue for the grower.
