John Kersten, November 2023
I have 200 fruit trees in a dry part of Australia and this is what I do to make water go further.
1. SIMPLEST WATERING SYSTEM
I draped rope strand from an old mop into a bucket of water. It wicked 7cm (2.5”) up the rope and started dripping over the edge of the bucket.
I got an old toilet cistern with a valve, connected it to my water tank (gravity fed) and drilled 10 holes around the cistern 20mm above the water level. I inserted 13mm poly pipe right-angle joins, fed the rope strands through them and ran the 13mm pipes to 10 different trees.
About 1 drip every 10 seconds equates to 1 litre/day – maintenance watering when I go away. No pumps or timers, just nature. A simple reliable way to water. Putting a another right angle join on the end of the pipe and adding a 20cm pipe into the ground ensures the water goes directly to the roots, making it even more efficient.
2. DEEP WATERING
When you just water a tree from the surface you encourage shallow roots. Which then makes the tree less drought-tolerant – so you then need to water it more often. Also, up to 30% of the water either runs off, gets absorbed into the mulch, or evaporates. I drive a sharpened 40mm thick stick into the ground on the tree drip line, and insert a 25mm pipe with a plastic bottle (with bottom cut off) fitted tightly (or siliconed) to the top of the pipe to act as a funnel. And just fill the bottle when the tree is looking a little dry.
Hand watering is much more water-efficient than even the best irrigation system. You’re checking your trees more regularly, and only watering the ones that really need it, thus, again, encouraging deeper roots. I find the process meditative, even therapeutic at times.
3. TURN 10mm OF RAIN INTO 40
A simple way to multiply rainfall, is to place old iron, plastic, old tents, or any other UV stable sheeting on the uphill side of a tree or plant, thereby directing the rain to the tree. It helps to get young trees established with less manual watering. If using canvass or plastic I shape the ground using forest mulch (easier than digging) so that it funnels to the tree. Also, the mulch and earth under the sheeting stays moist and therefore more conducive to microbial multiplication.
4. WATER FROM AIR
I’m intrigued by the “humidity harvesting” machines that pull water from the air, potentially changing life for many people in dry climates. Then I learned that I have plants here that do the exact same thing – cacti. Yes the ‘invasive weed’, Prickly Pear harvests water from the air via it’s thorns, storing it in it’s pads – which are 85% water. So by burying them around fruit trees, and in worm farms (see below) I’ve effectively been harvesting water from the air! As well as returning carbon to the soil. Brilliant!
This – plus the fact that they regrow quickly even in a drought, that cows readily eat the pads in dry times and that both the pads and fruit are quite edible for humans, should cause farmers to rethink Prickly Pear as a ‘weed’ and see it at least as a valuable means of feed, and of carbon restoration.
5. CACTI WORM STATIONS
I put a wheelbarrow load of cacti pads into my worm farm just to see how well they’d break down. I was amazed when 6 weeks later – with no added water – all I could see was worms and their castings, not even a trace of spines! Seems worms like the pads as much as cows.
I have since placed a number of 200L drums and half-drums throughout the garden and around trees, thrown in a few worms and cow manure and filled them with cacti and grass mulch. Worm stations throughout the garden. I placed some between two or more trees knowing the tree’s root fungi will find it. I cut/compress the cacti pads with a sharp spade to help them break down quicker, and top them up as the cacti every couple of months.
6. SHADE FOR TREES
When I get old tents from the tip shop (idea 4) I get the poles as well, which I use to erect a simple ‘shade roof’ over trees. I place 4 x 3m (10’) poles about 3m apart (leaving room to move around the tree). Triangular bracing with wire makes a surprisingly rigid frame. Shade cloth over top provides shade to the tree reducing water needs. Butterfly netting, bird netting, light shade cloth or fruit fly netting wrapped around it provides protection from various critters – and wind.
7. 200 LITRES OF BIOCHAR IN 2 HRS
Enriching your soil with carbon is possibly the best way to drought-proof your trees.
I made a biochar furnace out of a couple of 200L (44gal) drums. It makes 200 litres of biochar in 2-3 hrs (depending on the wood). I cut one drum in half vertically and placed old BBQ grates in the bottom to make a firepit. filled it with dry hardwood (for max. heat).
The other drum I packed with DRY wood, made reasonably airtight, and placed it over the firepit on two 50mm pipes. The secret is to keep as much heat around the drum as possible to ‘roast’ the wood inside so I built a sheet metal cover 60mm (2,1/2”) all around the drum to contain the heat to thoroughly ‘roast’ the wood inside the drum. And added a chimney on top. It gets super (glow red’) hot and the first lot was done in just 2 hours. When I doused the fire. I got 160L of perfect biochar from the drum and another 40L from the fire pit. I’ve tried different ways of making char but this is the best so far. Biochar is not only a ‘time capsule’ of minerals and moisture for plants, it’s a great way to sequester carbon back to the soil (correcting the earth-atmosphere carbon imbalance). Carbon is that magic substance that science can’t fully explain, adding to the humus that gives soil the magic ability to grow and sustain plant health beyond expectation.
8. CARPET CAPERS
I get old carpet from a local flooring shop for free. It makes good weed mat, plus it helps keep soil moist. Also great on paths (turn upside down for a ‘hessian’ look) and easier on the feet if you walk barefooted as I often do.
A 3.0 x 0.6 meter piece joined at the shorter sides makes a 1m wide circular, self-supporting breathable compost bin. I also fill them with cacti pads near trees (instead of drums) to provide water and nutrients to the tree for months. Lining the inside with plastic prevents it drying out. With some I place a 150mm tube in the middle of the cactus filled with soil, then pull the pipe out when full of cacti. Pumpkins go well in them as they have a long lasting source of water and nutrients.
9. AUTOMATIC WICKING BED
I prefer the above wick-drip watering system to wicking beds. But you can easily automate a wicking bed (so you never need to check the water level) by placing a valve (toilet cistern or other) in a bucket or other container beside the wicking bed. Then connect the reservoir to the container with a 13mm pipe so the water level stays the same in both. With a constant water level you only need a tiny reservoir; a concrete ‘v’ as below means you don’t even need to waterproof the edges.
10. CARBON HOLES
As a quick way to make biochar and other carbon-rich materials accessible to a tree, I dig a 50cm (2’) hole on the drip line of the tree and fill it with biochar/worm castings/cow manure etc and cover with mulch. On some I’ve placed a bottomless bucket (or carpet ring) and keep that topped up with food scraps or cacti to create a mini worm farm. Adding a deep-watering pipe directly into it (as in # 2) keeps it moist while watering the tree.
John is happy to answer anyone’s questions. Email: email@example.com