Automated Irrigation: Blumat Systems for Growing With ‘No Till’ and ‘Super Soil’

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Blumat is an automated drip-feed system.

Blumat essentially requires a raised gravity reservoir (5-15+ PSI), a pump (this needs to be a pump from the Blumat store, fitted with a compressor and a pressure reducer), or a tap (via pressure reducer, fitted to the tap, to maintain a limited water pressure through the feed lines).

The drip-feed is turned on and off, based on moisture content in the top layer of your soil. It has the potential to massively reduce the manual labour associated with an indoor water-only organics run; particularly with several plants.

All you need to do is keep a water reservoir full, or just have a tap free.

‘Super Soils’ and ‘No-Till Living Soils’

Both soil types revolve around microbes creating large amounts of plant nutrition in less soluble colloidal forms via breakdown/chelation of organic matter.

Super Soils generally contain enough nutrition for an entire grow. They require amending with organic matter and nutrition for reuse. You can set up super soils in smaller pots, to limit plant size and increase the mobility of the plant.

Biochar and worm castings can increase ion exchange capacity, available nutrition and microbial levels, as well as maintain microbial life.

Examples of ‘Super Soils’:

Organic Gardening Solutions
High Powered Organics
Dr Greenthumbs
Easy as Organics

Living soils work around creating a self-sustaining environment that can be used continuously without additional organic amendment.

A living soil requires a strong and diverse macro (earthworms, slugs, nematodes, termites, earth-mites) and micro fauna (fungi, bacteria, protozoa, algae, actinomycetes). A larger immobile soil bed is needed to achieve self-sustaining relationships between plant roots and microbes/insects.

Feeding Your Medium (and Plants!)

Feeding revolves around compost teas to stimulate microbial (and macro) life.

Cover crops such as ryegrass, rapeseed, hairy vetch, clover, lucerne and fenugreek will greatly improve soil structure and fertility. When planted at the start of a grow, they can help feed soil microbes, increase microbial activity of the soil, fix atmospheric nitrogen, and add organic nutrition to the soil via root pathways.

Some organic products may need to be intermittently hand-fed, rather than added to the reservoir, to avoid gunking issues in the lines over time.

Using the Blumat System

The Blumat system is powered by a ceramic cone (known as the Blumat cone, or carrot) which is pushed into the soil. It uses the same technology as in professional tensiometers. The more water pressure provided to the cone, the more drippers you can connect to each ceramic cone. The moisture content of the soil triggers an on/off valve in the ceramic cone, providing water from the attached drippers when the soil is sufficiently dry. A suction tension forms when the soil dries out, and this tension pulls down a valve in the cone to activate the drip.

The further the drippers are from the ceramic Blumat cone, the more water they will deliver before the soil is moist enough to have the valve shut the drippers off again. This can be used to increase or decrease water delivery, depending on VPD conditions or medium saturation levels. If the bottom of the smart pot is more than slightly wet, too much water is being fed. Move the drippers closer to the Blumat cones. Make sure to handfeed low and slow, or use nutrient wells under drippers instead.

In summer, some handfeeding may be required when it is hot, as the Blumat will stop dripping as fast as ideal when temperatures hit over 30 degrees Celsius.

Yucca extract can help in excessive temperatures – as can covering the soil surface with mulch.

“Nutrient Wells” – basically a hole +/- a vermiculite sponge ball

Used to feed bottled organic amendments that might cause issues in the water reservoir – either from interacting with other organics, or from creating gunk in the lines.

You can make a well/hole in the soil below a dripper and fill it with a vermiculite ball. Soak the feed, undiluted, directly into the vermiculite. The vermiculite acts as a little nutrient/supplement sponge, holding in the solution and slowly feeding it to the plant as it is watered by the dripper. For thicker nutrient formulations – like some molasses mixes – a well/hole dug in the soil, straight filled with the liquid, under a dripper, will be sufficient.

For a 10-gallon smart pot filled with soil, a Blumat system consisting of the following is recommended:

1 maxi cone
1 regular cone (+1 more regular cone for a 15-20 gallon smart pot)
5 distribution drippers

For a 5-gallon smart pot, the recommended is 1 regular cone to 4 distribution drippers (need high gravity pressure), or 2 regular cones with a dripper each.

If you forget to keep reservoir topped up and the soil and cone/s dry out, it’s important to properly re-soak the cones.

Hydroponic Amendments You Can Use in Your Indoor or Outdoor Soil Grow 

(Warning: Expensive, Optional and Probably Not For Beginners)

Stress Relief Products

Aloevate is a good microbe food. It also contains silica, enzymes, amino acids and yucca extract to protect your plant against heat stress. Aloevate works well as a foliar spray, promoting resilience to mould.

Marine CaMg has plenty of Ca and a big N hit. This is only for very occasional use in big plants, or if there is yellowing occurring. Its useful as a foliar spray to correct N, Ca and Mg deficiencies fast. It works well in combination with Aloevate.

Supernatural is a kelp:humic acids extract combo. It’s great for use throughout vegetative stage and until mid-flower. It’s also good as a foliar spray. Kelp contains the full spectrum of micronutrients, and greatly stimulates healthy vegetative growth and increased flowering sites.

Startboost is an amino acid source, and nocturnal beneficials source to supercharge a vegetating plant.

Flower Boosters

Biodiesel is an organic phosphorus and carbohydrate source. It also contains other Biostimulants. This is for use from flower formation through till main flower setting achieved, and bulking is starting.

Rhino K is a K citrate, for use during bulking and final weeks of flower.

Peakboost is an organic phosphorus source. Its use case is similar to biodiesel.

Finaleboost is an organic potassium source, to be used similar to Rhino K.

Cannaboost and Bloomboost are two metabolism boosters; to be used throughout flower. They boost fruit formation, oil production, stress resilience, and feed microbes.

Mammoth P is a microbial product, specifically designed to increase phosphorus uptake and general nutrient recycling, as well as nutrient availability in cannabis plants.

Terpinator/Purpinator is a natural oil and secondary metabolite stimulator, for use throughout flower.

Other Amendments (Less Expensive)

Biochar and worm castings (dry soil amendment by ‘Easy As Organics’)

High Powered Organics – Herb-Superb wet amendments

Dr Greenthumbs’ Go&Grow (vegetative) + Bud&Bloom (flower) – dry top-soil amendment

Root roids (microbial, vege), fish hydrolysate (vege), Fruit Roids (biostim, flower) –> Dr Greenthumbs’ wet amendments

‘Myco Inoculant’, designed to be used with drip irrigation and not clog

Aloe extract

Kelp, Alfalfa, Neem meal (vege, early-mid flower feeds)

Bat guano, worm castings, blood and bone meal, molasses, malted barley (flower)

Compost teas (throughout, especially important for living soil)

Avocado

Coffee grounds

Feather

Fish

Hemp meal

Fulvic/humic acids

Gypsum

Coconut water

Corn grain extract

Rock phosphate

Contributions from Mick Hardwood. Edited by Mitch.