Germination Guarantee
Free Shipping

Silica For Cannabis: How To Grow Healthy And Productive Weed Plants

November 4, 2022

Silica for cannabis is a uniquely ironic combination. While this nutrient makes up a significant portion of marijuana plants, it isn’t required for successful growth.

The astonishing part is that experiments that use silica supplements show undeniable benefits. This compound boosts production, increases bud size, and protects against pests and diseases.

Read on to find out how silicon can assist your weed crops. Discover what it is and when to use silica. We’ll also explain how it can improve overall plant health and maximize results.

Let’s dig in.

What is silica for cannabis?

Silica makes up much of the sandy beaches we laze on, forms the glassware we handle daily, and is one of the main ingredients in the earth’s crust.

Humans need silica to produce collagen in the body. The mineral is central to forming bones, blood vessels, tendons, cartilage, teeth, and hair.

Silica is a result of the element silicon coming into contact with oxygen. The chemical name is silicon dioxide (SiO2). It’s abundant in soil and reportedly found in 95% of rock types, especially quartz.

It also makes up a significant amount of organic plant tissue. Although the levels of this nutrient may be higher than nitrogen or potassium, silica for weed isn’t necessary for growth. As a result, many cultivators ignore the potential benefits, and there may be several.

silica for weed

Benefits of using silica for cannabis plants

Plants grown from indoor and outdoor weed seeds benefit from supplemental silica in several ways. The growth of sturdier cell walls creates bigger and healthier buds, and the complementary effects don’t stop there.

Here are some of the advantages of using silica for weed.

Improves nutrient uptake

Plants grow wider stems and more substantial branches with thicker cell walls. The latter contains the vascular system, the conduit for nutrients and water to move throughout the structure.

A healthier delivery system boosts maturation by delivering maximum nutrients. It allows optimal absorption of crucial minerals like nitrogen, magnesium, and potassium in cannabis.

It also lowers the potential for a nitrogen deficiency in weed, reduces phosphorus levels and stabilizes the levels of potassium, promoting healthy reproduction and growth.

Magnesium is vital as it turns light into energy. If the plant doesn’t receive enough of this mineral, there may be an adverse effect on bud production and yield.

Makes stronger cell walls

Cannabis plants grow stronger walls when they take in silica. More muscular walls mean a thicker stem and bulkier branches that can support heavy loads. They also transfer more water and nutrients to where they’re needed, which translates to rapid vegetative development.


Increases resistance to environmental stress

Plants treated with silica for cannabis survive extreme conditions better, whether heat stress or cold. This trait is handy for outdoor cultivators who may deal with baking midday highs and chilly overnight lows.

Silicon dioxide can also help during drought, reducing water loss by controlling the stomata and the transpiration process. It allows plants to function during dry periods with high or low temperatures without going into shock.

Increases resistance to pathogens

Growers report silica for weed plants lines the cells like a cloak, making it more difficult for diseases to gain access. It provides an effective barrier against pathogens and helps reduce the potential for powdery mildew, mold, and other issues.

Defends weed plants from pests

Silica gathers in leaf skin walls, strengthening them and making it more difficult for pests to bite or damage the foliage. Applying silica in a foliar spray deters sap suckers, too.

defend weed plants from pests

Improves yields and makes buds bigger

A silica supplement for plants increases the nutrient intake speed. It results in quicker growth rates and larger plants.

Larger structures usually come with more voluminous nugs. A healthier plant is more vigorous and likely to produce other bud sites with more dense, high-grade flowers.

Enhances metabolic functions

In scientific tests, silica-grown weed shows higher chlorophyll concentrations than non-silica plants. It creates more energy for the plant and offers efficient carbon dioxide processing. 

Plants grow lush, green, and bushy with a strong structure and many leaves. They produce greater concentrations of terpenes and cannabinoids that medical marijuana users covet.

Prevents uptake from toxic heavy metals

This compound protects your plants from soil contamination by blocking the uptake of heavy metals. Scientists have reviewed several experiments, concluding that silica reduces the bioavailability of:

  • Chromium 
  • Lead 
  • Aluminum 
  • Mercury 

These heavy metals can interfere with photosynthesis, prevent the uptake of nutrients, cause yellow leaves, and even kill plants. Silica significantly reduces their uptake.

How and when to use silica for weed plants

Most growers use silica for cannabis in soil-based grow systems, but it’s also suitable for hydroponic setups. Most supplements are root additives, but there’s also a growing list of foliar sprays.

Silica for soil

Your soil is a living medium containing various microbes and bacteria. Some assist cannabis crops, but others cause problems, and silica might be the surprise cure. It helps protect against outside threats, increases productivity, and shields against toxins.

Keep in mind that silica is alkaline and could increase your substrate pH, so test before and after and adjust when necessary.

The crops absorb the compound via their roots, and what’s left remains in the soil for later use. Start feeding silica for plants in soil early in the vegetative stage. It strengthens the cell walls and promotes big, strong branches, stems, and crops.

Add potassium silicate to water for outdoor and indoor cannabis seeds. It’s usually in powder form and dissolvable, but liquid varieties are also available.

Mix about 4.4 ounces of powder for every 2.6 gallons of water, depending on the brand of potassium silicate you use. Liquid versions typically require 2–3ml.

You can use silica as often as your other nutrients or less. Plants grow fine without silica, so underfeeding isn’t typically a problem. It could even help by maintaining the pH balance of your medium.

Its vital to stop adding silica when flowering commences. While you want a durable structure, you don’t generally wish for tough flowers. Using silica supplements during the flowering period will harm the quality and size of your yield.

Kyle Kushman watering plants

Silica for hydroponics

Hydroponic plants can be weaker than soil-grown ones due to a lack of silica. The compound is alkaline, and you can’t store it in the acidic environment of a cannabis hydro garden. 

Prepare your silica for hydroponics solution separately to optimize the pH level before including it in the main marijuana fertilizer mix. It can be a time-consuming exercise that requires a great deal of water. However, the gradual addition of silica prevents nutrient lockouts.

The most significant worry for hydroponics is the potential for pH changes that can seriously affect your harvest. If the pH rises too much, the solution turns cloudy, impacting nutrient uptake, stunting growth, and perhaps worse.

100ppm should suffice in a hydroponic setup. Add silica for plants as often as your other foods. Remember, it’s not one of the 17 essential nutrients required for cannabis cultivation, so make sure it doesn’t compromise your harvest.

Used correctly and in moderation, silica can inflate your hydroponic yields and improve the health of your buds. 

It can also come in handy after the harvest. Silica packs remove moisture from the air, which can be helpful during drying. It speeds up the process, protects the trichomes, and reduces the potential for mold or mildew. 

FAQs about silica for weed

Growers are fascinated by the benefits of silica for weed plants. We answer a few of the most common questions about this compound below.

Can you overfeed your plants with silica?

An excess of silica can throw your pH out of whack in hydroponic setups. The solution turns cloudy, and nutrient uptake is affected. It’s a delicate balance to maintain, but the rewards are worth it.

The same thing can happen in soil, although plants typically take what they need from the ground. A high pH in the growing medium doesn’t help your harvest and may cause nutrient lockouts or deficiencies that hold back growth.

Should you use silica during flowering?

No, you shouldn’t. All the advantages are made redundant by feeding your plants silica during flower. Although it makes the buds more resilient, it also diverts resources that could enhance the development of valuable terpenes and cannabinoids.

Can you mix silica with other nutrients?

It’s best to store silica for weed separately from other nutrients or marijuana fertilizer. It requires an alkaline pH of higher than seven to remain soluble. Only add silica to a nutrient mix right before you apply it.

Does silica help weed growth?

Scientific tests show the best silica for cannabis aids vegetative growth. It strengthens cell walls, which grow wider stems, allowing larger pipelines to transport higher volumes of nutrients and water.

When do you stop using silica?

Experts aren’t entirely in agreement with this answer. There are three positions:

  • While some think you can use silica for cannabis from germination to harvest, a few users complain of unpleasant flavors. 
  • Others claim waiting till halfway through the flowering phase is best, allowing for a rinse. 
  • The majority believe silica for weed plants is counterproductive once flowering starts. It tends to impact bud creation and quality negatively.
healthy cannabis plant

Silica for cannabis summed up

While silica isn’t an essential nutrient for cannabis growth, it acts like a multivitamin and boosts functions at a cellular level.

The crop structure solidifies with more substantial building blocks, and the highways transporting nutrients get more lanes. Plants resist pests and disease to produce healthy, dense buds. Use silica for cannabis to boost quality and output.

Buy your epic cannabis seeds from Homegrown Cannabis Co. and use silica to add weight and worth to your output. We have over 500 incredible cultivars available, making us the most comprehensive stockist of quality strains in the USA.

Was this article helpful?
Do you need help? Contact us
Leave your comment
Your email address will not be published
  • Be first in line to hear about our amazing deals and new products.
  • Learn how to grow cannabis with expert tips, tricks, and hacks.
  • Watch strain reviews, podcasts, and more.
This website is intended for adults only (21+)

Are you over 21 years of age?