Saturday, 1 November 2014

From dripping with sweat to drip irrigation

We've had a scorching heat wave over the last week or so which shows no sign of relenting.  Nearly 40 degrees in October is just ridiculous but unfortunately sets precedent for the long summer ahead.  To top it off we've only had 2.8mm of rain this month, leaving the grass crispy underfoot and tree leaves sagging in exasperation or just quitting altogether.

Having placed the orchard right at the front of the property to provide screening from the road and room for expansion, the thought of irrigating it didn't feature too high in my plans.  While that was fine over winter and the start of spring, bucketing water 200m each way, every second day during the current heat was not appealing in the least, let alone a feasible option unless I was planning to construct myself a yoke.  Irrigation was fast turning into a regular irritation.

The IBC.  You can also tell how dry the grass is (or lack thereof) in this shot.
After much deliberation, we decided a yoke was probably not the most appealing option.  We finally bit the bullet a couple of weekends ago and bought an IBC (international bulk container) second hand from a local as water storage for the drip irrigation system.

Our current pump is overkill for our needs (it came with the house and is technically a firefighter pump) so we attached some new irrigation pipe to another from one of the pump's four outlets up to the IBC to fill it and installed a float in the tank to cut off the flow once it was full.  It felt like we were doing the chicken dance with the number of elbows involved in attaching it all and creating the appropriate bends in the pipe.  I probably looked like I was doing the chicken dance too, hopping from one foot to the other trying to keep the ants from dismantling the flesh on my feet.  From the IBC the drip system is gravity and water pressure fed via a standard garden hose connected to the drip lines (yet more elbows and a T piece for something different).  It was surprisingly easy to set up, bar a gender mix up on one of the fittings, and it was done in one afternoon.

 We've only got two rows in the orchard so far.  The trees are lapping it up and are even starting to put on new growth after just two deep waterings with the drip irrigation!  The tank empties surprisingly quickly but at least the water isn't running off down hill and being wasted.

New growth on the mandarin which dropped most of its leaves in protest at the change in temperature.

Once we add more rows the water will be spread more thinly but hopefully the soil will have improved more by then to retain the water.  We're planning to build up the soil in between the plants in more of a swale style, then adjust the irrigation to be on the uphill side so it soaks into the mounds.  When we get a wet summer again this should also help the heavy rain to soak in and down rather than strip any more of the topsoil and silt up the dam.