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Micro-Climates, Calcium Deficiency & Nutrient Timing

Sherb N' Runtz Sunset Sherbet x (Runtz x Strawberries & Cream F2) | Bred by 808 Genetics | Grown under 1500 watt A3i By @hairyhippyfarms & @absolute.chronic.farms | Photographed by


Today, we are featuring a few topics covered recently on the FOHSE podcast that I thought was relevant to both amateur and commercial grows who are working to utilize the most space in each room without sacrificing quality.

Legal cannabis is becoming more and more popular, therefore grow facilities are becoming larger and larger. This is leading to what are known as multi-tiered systems where one room houses multiple tiers of canopy, sometimes more than two. This is very ambitious as it becomes more difficult to control the micro-climates at each level of the room, regardless of air flow techniques used to maintain the climate of the room.

What is homeostasis for the bottom tier will not be the same for the top tier in the same room. Therefore, it’s becoming more important to sample different canopies of the same strain separately to understand the nutrient uptake and vitality of the individual plant. This becomes an issue if facilities combine multiple samples of a strain from different tiers of a room into a testing bin for the room. This negates the data from each individual section in the room and its individual climates.

If you’re doing analysis in a facility or at your own home and you have repeatable results, then one of the variables to correct is to start collecting more efficient data points.

Within a double tiered environment you get stratification as you go up in tiers, as air flow changes, as temperatures differ. So how much variance, hypothetically, between a Wedding Crasher, or any strain, grown on the bottom tier and the top tier of the same room?

We are talking about situations where people are trying to replicate the exact same environment and the exact same feeds through an entire multi-tiered room, which are almost impossible. There’s a nuance to climate right?

Absolutely! In one room with four different strains, you wouldn’t take samples from all four strains and put them in one sample lot, because that would wash out the data. The same applies for the same strain, grown in different tiers, in the same room. In order for micro-climates to be tracked, data must be kept separately.

If the strain on the bottom tier is hyper aggregating phosphorus and the tier above is short on phosphorus, and you put the two points together into one sample, you wash out the numbers so you don’t know which one is deficient and you don’t know which one is hyper aggregating.

In a multi-tier system, the microclimate between the lower tier and the upper tier are totally different. I don’t care what anybody says. It doesn’t matter what kind of hyper-futuristic air flow system you have rigged to balance the air mechanics.

If you’re in a multi-tier system, the micro-climates will vary throughout the room. Anyone can convince me that they have the world’s most sophisticated air flow system, but there are microclimates and so we must sample each section separately for accurate data. You will always see differences between the two different tiers within the same room.

By properly collecting and sharing colleague data, along with empirical evidence, FOHSE is helping any gardener better monitor grow rooms by considering known variables.

Calcium Deficiency & Nutrient Timing

In this second part, let’s briefly touch on calcium deficiency, which is a common problem for cannabis grows.

Q: Is it because the nutrient formula is lacking or is the variety a hyper aggregator of potassium or is the nutrient lockout occurring due to an excess of potassium in the feed?

A: Peppers are known for being hyper aggregators of potassium. The way to control that is to increase manganese because manganese regulates the uptake of the potassium. It’s not that the calcium is not there, but it’s being blocked by the potassium uptake because it’s hyper aggregating it. The only way to control the uptake of the potassium is to increase manganese uptake. Once you get manganese to a certain concentration in the sap, potassium falls back and you open up the door for the calcium to come back in.

We have to make sure that the plant has nutrients at the right times. If we get phosphorus to the plant too early we can get really stretchy plants. For example, when phosphorus is given to Tropicana Cookies too early on, if it’s too much phosphorus, a strain like Tropicana Cookies will stretch terribly and you’ll get six to eight inch inner-nodes.

Hold back on the phosphorus pump until plants show flowers and when you actually see the flowers, then add the phosphorus. Flowers are usually an indication that the plant is strong enough to handle pumping phosphorus but for those particular strains like Tropicana Cookies, you just won’t get there if you start adding it too early. That’s why we have to make sure that the plant has nutrients added at the right times, not just in the correct amounts.

FOHSE is the number one LED producer, engineered specifically for cannabis, in the USA and they have grown at an incredible rate globally within the last few years. With access to the most premier grow facilities in the country, we have been fortunate to have FOHSE as a partner source of data for our readers. The team cares about the experience of the end cannabis product. They are cannabis nerds too.

For more concepts from this podcast, visit FOHSE.INC on Instagram or Twitter. Photograph by


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