What makes foliar feeding so special and an excellent way to address any type of nutrient deficiency is that spraying is much faster compared to applying nutrients to the soil via irrigation. The majority of the nutrients that you spray directly on your plants’ leaves will be absorbed in a very short time. The plants will also take in a much higher percentage of the nutrients this way. Studies have shown that foliar feeding is as much as 95% effective. This means plants take in almost all nutrients administered by spray, while they uptake a smaller percentage when fed through the soil.
Many other natural ingredients, from cayenne pepper to nettle, cinnamon oil, and even plain milk can help combat powdery mildew and other fungal pathogens naturally, without causing any harm to your plants. If you look around on grower forums and websites, you can find many recipes for such natural foliar spray mixes.
Avoid spraying when it is too hot or too cold. In hot temperatures, your plant’s stomata (the pores in the leaves) will be almost closed, making a foliar spray much less effective. On the other hand, when it is too cold, spraying could promote fungal growth. Spraying early in the morning can be best since this allows your plants to dry during the day, reducing the risk of mould.
When you spray, spray the entire plant – in particular the undersides of the leaves. There are at least two good reasons for this. Many pests, such as spider mites and other aphids are often located on the leaf undersides. This is also where more of the stomata are located.
One type is a simple hand-sprayer that may take 500ml to 1l of spray solution. These small and handy sprayers are great if you only have a few plants or if you require a sprayer for some “precision work;” for instance, when you want to avoid spraying buds.
The other types of sprayers are garden pump sprayers. These come with different capacities and a shoulder strap so you can carry them around easily while attending to your plants.
A foliar spray made with potassium soap (insecticidal soap) is an excellent option to take on and then take out various harmful insects. It is particularly effective against aphids, which are some of the most common cannabis pests. A mix of neem oil dissolved in potassium soap is doubly effective. The potassium soap gets rid of the pest on contact, and the neem oil helps prevent future attacks while strengthening your plant’s defenses.
There are two main types of sprayers available that you can use for foliar sprays; both types are useful depending on the circumstances.
The best is when you get both types of sprayers so you have them handy when you need them. There will always be times where the bigger pump sprayer will be better to use and then there are situations where you want the small hand-sprayer instead.
Learn about how and why to foliar feed your cannabis plants. What makes foliar spraying so effective and how do you get started?
To use foliar feeding correctly, you’ll first need to understand a few foundational tips and tricks.
Stomata are not always open, which limits the time frame in which you can apply your nutrients. Most gardeners advise that you spray in the evening time. If growing indoors, the stomata will take about 15-20 minutes to close up after the lights turn off, which gives you time to apply the nutrients without stressing the plants. Outdoors, you can start spraying in the late afternoon when the sun is descending and not directly hitting the plants.
Protect your garden by first spraying one plant and see how it responds before you spray other plants that look ill. Note that the damaged leaves will not recover, but new growth will appear vibrant and strong, and aging leaves will appear more colorful.
Once again, if you notice any plants showing signs of nutrient deficiencies, foliar feeding is a great solution. Plants most commonly display calcium/magnesium deficiency or a nitrogen deficiency, which can be remedied with a quick foliar spray.
When to Use Foliar Spray
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How to Foliar Spray Cannabis
Foliar feeding can also be used as a preventative tool to keep your garden thriving. This is accomplished by applying an array of macronutrients that will help provide your plants with a well-balanced diet.
Some nutrients give advice for how much to dilute their solution; others do not, so it is recommended you start low and work your way up. If your plants are young, use 20% of the recommended strength for liquid feeding per gallon. As the plants grow larger, you can increase the percentage while observing how your plants respond.
Foliar feeding is a process that can help plants absorb nutrients quickly. Learn all about how to foliar feed your cannabis plants to help them grow healthier.