Root zone temperature anyone?

We have nutrient delivery system customers using soil (without recirculating) and coco as well as rockwool, mostly with recirculating which adds a different dynamic to the irrigation (micro-NFT effects and enzyme production, but primarily helps with establishing biologicals in the rhizosphere compared to drain-to-waste systems). Our method/feed formula though is tuned to rockwool cubes.

Each media has its own characteristics regarding pH stability, wicking, moisture holding and support for the rhizoshpere microbiome development, so the overall irrigation system and growing method needs to be tuned to that for optimum yield/quality.

Soil is the most different where you are essentially feeding the plants indirectly through the soil and rhizosphere microbiome. Here is some quite useful information regarding management of the latter for optimum yield:

http://libcatalog.cimmyt.org/download/reprints/93832.pdf

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@JoeGrow Thanks for the info; it’s gonna take me a few days to get through it :wink: - but it is pretty interesting. It looks like it does a lot - seems like a pretty complex system; is the learning curve on it pretty steep?

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@greg.s , I presume you are asking about our recirculating nutrient delivery systems. In my opinion, they make growing quite efficient and allow you to spend more time with your plants and/or family as required - especially when our rockwool growing method and custom tools are adopted as well.

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Have you looked at the SmartBee Controllers Irrigation Bundle? This system has the ability to track moisture content in your medium as well as root zone temps all served up through a web app to your phone or computers from anywhere with an internet connection. http://www.store.smartbeecontrollers.com/irrigation-base-system/

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Here is a link to another thread talking about the data:

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Thanks for the info; I’ll have a look - I’m pretty sure our system works with SmartBee - we talked to them at some point. But it can’t hurt to know more!

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Lots of traditional glasshouse growers water with pre-warmed water. In Europe, I would see big growers using flash hot water heaters. Made large difference in production times of more traditional crops.

With the price of flash heaters coming down in price it makes sense to try. If you are heating a production facility, why not heat your water?

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I agree with Ethan, water temps are an often overlooked factor in controlling root health.

If plant roots drop below 50F, they stop growing. Below 40 they start to die. Above 70, the oxygen holding capability of water starts to drop precipitously, and can cause root rot.

If the plants are wet and cold, you’re probably watering too often. In the winter they’ll drink half as much as in the hot summer, so nutrient levels often need to be increased. As long as the plant is under 4 weeks in flower, they are still growing roots and don’t need tons of water. I’ve cut mine from 3x 30 minute waterings a day to 3 waterings a week, and may cut it further. I also use coco and perlite, bit adjust the ratio in winter so it’s 83% perlite.

Heating your reservoir to 70* will help prevent cold stunting their growth, but if your medium is holding water after 1 day, you need a lighter medium. Something that dries out quickly so you can water again with warmer water will help you get better yields over the winter than fighting to make your “summer mix” work.

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The DWC people recommend 68F and not to exceed 72.

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