Watering strategies in the midst of severe drought

Hello everyone--

We're trying to keep some 1-2 year old fruit trees alive in Northern California this summer in the midst of severe drought conditions. I have 5 apple trees, 2 paw paws, a jujube, apricot, loquat and nectarine along with some seaberry and goumi berry bushes. They are all planted on a swale system and I did have some drip irrigation in place just to help establish them with an end goal of weaning them off in a couple years.

Extreme drought now prevents us from using any city water to irrigate as official policy, which is moot because the pipe is dry anyway.

We have maybe 300 gallons of rain water we harvested last year and I intend to work hard to expand our rain water harvesting capacity before the rains come, to whatever degree they come, this winter.

Questions:
1. Any recommendations for how to best deliver the water we have to these young trees? I was thinking about finding used milk jugs and making a small hole in the bottom to function as a temporary drip system in the interest of limiting loss to evaporation and run off but I know these break down pretty quickly-- any other creative solutions?
2. What's the minimum water use to get these trees through the summer with 90s to low 100 degree weather for the next 2-3 months before cooler, wetter weather arrives?

Thanks for any insights!

Blaise

Blaise Waniewski wrote:used milk jugs and making a small hole in the bottom to function as a temporary drip system in the interest of limiting loss to evaporation and run off

I had some similar drought issues last year and did exactly this. Almost- Milk jugs are good sized but as you mention, break down fast in strong sun (I guess you could cover them in a paper bag or fabric if you really wanted to use them). Worse, I think they don't make a good enough seal to slow drip down enough. I ended up using scrounged soft drink bottles, which seal really well to get a nice slow drip; if you can find 3L that is a great size and should save you headaches filling up so much. I also can find 5L (1.5 gallon ish) containers for dish soap that restaurants discard, they also work well. If you can scrounge these things, even lidded buckets with a nail hole might work perfectly-- because the devil is in the filling. Filling 25 3L bottles with a funnel is a PITA.
I ended up doing mine about twice a week for young trees I have in pots, but I'm in a very different climate and not familiar with all your species. My other suggestion would be mulch them as much as you can to keep that moisture in, once you have it in the dirt.

My strategy here in the New Mexico desert is to combine heavy mulch and condensation methods to conserve water in fertile sunken “islands.” Now that the trees are 3 years old, I don’t water near the trunk. I water the drip line at the depression /swale using grey water on laundry day.

The basic approach is to dig depressions and swales then surround them with semi-dwarf fruit trees. The moist mulch and stone rich depressions are gathering places for leaves and wind-borne debris. They are rich with humus from earthworms that multiply in these depressions and aerate the soil. The roots reach toward the moisture and fertility provided by the heavy mulch.

But here is the secret for summer’s heat!  Elevated about 6 to 24 inches above the depressions (to ensure airflow to the soil), I put recycled impervious umbrella-like structures. Instead of filling the plastic recyclables, the water evaporates, condenses on the plastic, then drips back down into the swale. The dome-like structures are impermanent and improvised so that I can recycle whatever is available: upside-down kiddie pools, bubble-wrap, impervious tarps, plastic table cloths, oil cloth, upside-down 1, 2, and 5-gal buckets, old bowls, upended bird baths and garden pots. I conceal the upside down objects by nestling them into the mulch or surrounding them with native plants, trimmings and other organic material. The look is very natural.

Despite the drought, we’ve had good harvests of cherries, apricots, and plums. If all goes well the green peaches, nectarines, almonds, pears, apples, jujubes, and prune plums will ripen and provide more fruit in the coming weeks.

I'm not sure this is directly helpful, but ...

In situations where water under pressure is available, I've had good results using a deep watering wand. This is basically a thin metal pipe with a series of tiny holes near the watering end, and a hose connection and shutoff valve on the other. I push the wand into the soil about 12-16" deep and throttle down the water to a dead low minimum flow. I have made wands out of plumbing copper pipe, downhill ski poles, all sorts of stuff. If your water (like my well) has a high level of dissolved solids, it does not seem to bother the trees/plants like surface watering does.

This thread offers several suggestions:

https://permies.com/t/138768/Water-Plants-Trees-Drought-Conditions

Hi Blaise

I feel for you. Here in Australia we recently came out of a terrible 4-year drought. Where I life is dry subtropics, with little rain for about 8 months, and then a Wet Season during summer (with one big flood event annually).

We had the dry dry winters, but the summer rains hardly came. The grass dried to golden (as is normal), then to grey as all nutrient drained out, then it all turned to dust. Trees became sticks. The final summer there was one heavy rainfall lasting just over an hour. It had enough wash off to fill our dam, but there was no flooding (we are usually cut off from town for a day with the flood event).

This drought led to those terrible bushfires, when it is estimated about half a billion native animals were killed in the flames.

We are having a really wet year, so I am very thankful. But I know the drought will return sooner or later, and I can see the climate is changing.

I found the one thing that helped new trees survive was to create an underground compost heap. Above ground, everything was dry and would not break down. My husband has a post-hole digger for his bobcat (small earthmover) and he dug a post hole as deep as possible. I threw in whatever organic material I could find: paper, cardboard, hair, manure, veggie scraps, sticks, wood, cotton fabric - anything. I then filled the dirt back in, leaving it lower than the surrounding soil and planted the tree in there.

I made the dirt into a saucer shape with no lip on the uphill side and a high lip on the bottom, so if there was any rain runoff, it would flow into the saucer around the tree and get trapped there. I also mulched with paper or cardboard and a couple of rocks on top to keep the soil shaded around the roots, and to retain any water I put on. If I had made the saucer shape well, the paper could all slope inwards towards the tree's little trunk, for water runoff too.

The seedling trees planted this way survived the horrible drought, while others didn't, and a number of them have grown faster than trees planted in earlier years without this method.

Apart from that, I put paper/cardboard mulch around the roots of trees already there, and put a big bucket in the shower so all shower water could be lugged outside and go on the garden (we live on tank water). I got pretty sick of that.

How do you keep the holes in the pipe from getting clogged with dirt??

I love the deep watering wand, and the inverted self-shaded hollow moisture condensers. These are solid ideas, as is putting a watering reservoir upflow of each tree.

I have some observations. I feel that one could maximize the potential for soil surface moisture condensers if the main structural element was an unglazed clay pot, like a terra cotta flower pot, complete with drainage hole.

One could probably make a really white goatmilk paint, or use some other really white pigment, on the exterior of the pot to keep the inside of the upside-down pot cool, so as to increase its capacity to condense moisture out of the air. Airflow from the slight chimney effect would then evapourate condensate, cooling the terra cotta, maintaining its ability to condense moisture out of the air.

If opaque stones (probably not quartz) were stacked or piled up around inverted flower pots in a similar manner, with an mind to airflow, they would also keep the pot cool, creating what is, in effect, a miniature airwell.

I was actually wondering about things like lengths of small culvert half-buried, widthwise, in the ground as a sort of ground-based heat exchanger. If you could bury most of one footing deep enough, what remained above ground would be cooled by the ground itself. Pair that with, say, a hedgerow or some other type of planting that would shade the structure from solar gain, and you have ground-cooled, plant-shaded metal exchanger/condensers in rows, condensing water out of the air whenever it's there, delivering water like a drip line.

But you need moisture in the air for that to work. I love the reservoir angle, but I would use pairs of terra cotta flower pots with a plug put into place in the drainage hole of one, and the two pots glued together into a single vessel with clay of some kind (from the ground, hopefully), rim-to-rim, with the plugged bottom drainage hole downward, and the top drainage hole acting as the reservoir opening.

I take my paired flowerpot vessels and bury them upflow, or uphill, of my trees. They are a good slow-release mechanism, though in some cases I end up dropping wicks into the reservoir and curling the ends of those around the dripline of trees and shrubs to augment what was moving through the unglazed pottery.

As to underground composting, I love it. I would, however, keep it to the dripline, or perhaps between the reservoir and tree, right next to the water source. While I would place wood at the bottom of a particularly deep tree hole, this would be for drought resistance from establishment. Having a buried nurse log beneath it would regulate moisture all on its own. I wouldn't build a compost within the hole and then cap it with a tree. I like to think of it as incenting the roots to seek moisture and nutrients away from the tree, deeply into the nurse log, for instance, or outward for the compost nutrients and water.

As to less-intensive methods, you could get a lot of 2" or larger river stone and pile them in at least two, maybe three layers atop the soil surrounding your trees, the top layer would again keep the bottom layers cool, causing any moisture flowing through to condense out into the lower layers and drip onto the sheltered soil, which itself would evapourate less moisture.

A big rock on the sunward side of the stone mulch, just large enough to cast a shadow most times of the day over most of the stone mulch, would keep it cooler, thereby condensing out more moisture. Drought-tolerant plantings on the sunward side capable of shading out the stone mulch would also work. I would suggest drought-tolerant nitrogen-fixing bacteria host shrubs, something that will also tolerate your wet season, and can be pruned regularly for mulch and to control the solar aspect.

Getting plants or other structures to shade the mulch from the afternoon on at very least should allow you to maximise the capture of the dew cycle.

One last thought; one technique to get water from the environment in survival situations is to put collection bags around entire tree branches to capture the products of their respiration. If you could tent your trees, you might be courting other problems if they're too tightly wrapped, but otherwise, a tent structure pinned to the ground around a tree or trees might serve to trap some of that tree sweat in the air trapped around the trees, preventing them from drying out so much. And again, in cases where the tent membrane cools more than the ambient air, inside or out, there will be condensation if there's moisture in the air.

So yeah, if you could tent them and still allow for adequate airflow within the tent(s), the severity of your issues would decrease. You have hothouse greenhouses for four-season growing in temperate climates, why not moisthouse greenhouses, to keep our plants growing through seasonal drought?

-CK

Estamae Rose wrote:How do you keep the holes in the pipe from getting clogged with dirt??

If you are referring to my watering wands, the water pressure does it for you. I've never had a problem.

Amy Gardener wrote:My strategy here in the New Mexico desert is to combine heavy mulch and condensation methods to conserve water in fertile sunken “islands.” Now that the trees are 3 years old, I don’t water near the trunk. I water the drip line at the depression /swale using grey water on laundry day.

I think this is a great idea.  Instead of letting the wash water drain into the sewer/septic system let it collect into a large containers and use it for watering trees and plants.  When/if I get caught up on all my other projects I plan to pipe the gray water from the laundry to an area of trees near the back door.  If you need more you could wash dishes in a dish pan and rinse them over a second dish pan.  If you have a dish washer you could collect that water too but I wouldn't store it inside, use it right away and probably in an area further away in case the food bits attract critters.

Chris Kott-- Terra cotta pots with stones inside was exactly what I was thinking of trying out! Not sure how effective they would be but there's one way to find out.

As an aside, the milk/water jugs with small holes in the bottom, using the rain water we collected last season seems to be adequate for the time being. It's a solid temporary solution but long-term it will take a multi-faceted approach for when the drip line runs dry.

Hello Michael. You mentioned containing the laundry water:

"Instead of letting the wash water drain into the sewer/septic system let it collect into a large containers and use it for watering trees and plants.  When/if I get caught up on all my other projects I plan to pipe the gray water from the laundry to an area of trees near the back door.  If you need more you could wash dishes in a dish pan and rinse them over a second dish pan.  If you have a dish washer you could collect that water too but I wouldn't store it inside, use it right away and probably in an area further away in case the food bits attract critters"

Actually, the strategy is simpler:  I drilled a hole in the bottom of my utility sink then attached a ball valve with open/close option and a hose bib. On laundry day, I attach the garden hose to the hose bib then open the valve. The water drains into the swale outside the door. I also dump the kitchen water into a bucket strainer that sits in the utility sink when the hose is attached to catch the food for the compost. The kitchen water also runs through the garden hose and feeds the tree roots that reach toward the swale. So far, the critters don't bother this swale.

Thanks for your interest! Amy