Lessons from Snow in our Urban Desert

 

I woke up to this view from my front door. Snow in Tucson!  This is the second time we have had snow this winter! This is the epitome of what Katherine Hayhoe termed "Global Weirding!" Maybe I'm exaggerating a bit. But it is weird. It is rare for it to snow in our desert town.  

I like to fancy myself a "citizen scientist" taking pictures to investigate what is happening in our garden and desert food forest. So out I went this morning with my cellphone to take pics of the snow. Here are the lessons I learned. 

The snow on the gravel or bare dirt has already melted. But where we have native plants (that some people call "weeds") or organic mulch in the catchment basin, the snow was still on the ground. I noticed that there was no snow left where our neighbors have gravel or just plain dirt in their yards. That demonstrates just how much heat gravel holds. But I already knew that from going barefoot when working on my yard in June. I walk on the horse purslane mulch to keep my feet from burning. 

I found a similar development in the easement behind our house. The snow is sticking to the desert mustard on the ground beside our garden. Notice that the snow isn't sticking to the ground in the garden perhaps because the palo verde branches that shelter it from the summer sun also shelter it from the cold. Note that there are no "weeds" in the garden. 

See the snow on the bunch grass in our jujube basin? As the snow melts it is another source of water for the plants and trees in our basins. 

Our native desert trees and bushes have adapted to the occasional freeze and snow storms. In fact, the hackberry in the mesquite guild (below) and our wolfberry in the right-of-way basin seem to be thriving in the snow. The organic mulch helps.  

Then I investigated what was happening in the backyard. The snow was already melting into the greywater basin supplying water for the heritage fruit trees there.

As anyone who has a cistern (rain tank) knows, we get lots of rain off of the roof.  Now our cisterns are overflowing from the snow melting off of our roof and the neighbors' roof. 

snow on our neighbors' roof

snow melting into the cistern

The cistern overflows into the garden...Sheltered by the branches of the palo verde, the chard is doing fine. 

Reminds me of how the snow melts on the Catalinas, rushing into our desert streams to nourish the surrounding trees and riparian habitat. 

view of the top of our watershed - the snowcapped Catalina Mountains

Here's what I learned from my little citizen science project this morning:

I learned that ground covered with gravel retains more heat so the snow melts. But without a catchment  basin to gather that water for a nearby tree, the water is often wasted. (Though the water can sink in under the gravel to water a nearby plant if there is no plastic preventing it.)  In our yard, the native grasses and organic mulch allowed the water to slowly melt into the catchment basin to the benefit of our native trees and bushes. I observed how the snow in our greywater basin melted into the basin to water our heritage fruit trees and how the snow on the roof melted into our cisterns filling them up to use on our garden and landscaping.

Who knew we had a "snow water harvesting" system?! In the desert! How great is that!? 

Harvesting and Prepping My Winter Garden for the Freeze

Brr... Holding this ice is cold....

After some winter rain, we had our first frost and then deep freeze in Tucson with the temperature getting as low as 28 degrees at night. Yesterday I woke up to find frost on our purslane mulch and ice in the bird baths. 

A few days before, I started harvesting and preparing for the hard freeze. It was past time to harvest my sunchokes (or as we affectionately call them "fartichokes.") The stalks and leaves were all dried up, and some of the roots were breaking through the ground and turning purple. 

 So I pulled the stalks up with the roots. Check out all the edible tubers! 

Can't tell my fingers from the tubers, can you? 

I was so excited that I called my neighbor Julie over to look. She took this pic for me. 

She got a taste of the oven-roasted sunchokes we made for dinner. 

I also picked some red chiltepins (leaving some for the birds.) I had given the last batch to Uncle Rick. 

The next day I harvested most of the moringa tree and hung the branches out to dry for tea. 

I grabbed some leaves and a handful of pods to make moringa soup (using broth I had made from kitchen scraps of onions, celery and carrots.) 

I'm afraid that didn't leave much left on our pour moringa. Just some of the smaller leaves, flowers and pods. See the leaves drooping after the freeze... I hope the seeds are still good in the bigger pods. From past experience I know that most of the trunks and branches will die in a hard freeze. We will eventually prune them down to about six inches. 

But don't worry, in the Spring they always come back from the roots. I like to give them the best chance by wrapping insulation around the bottom of the trunk. 

Next I tended our little winter garden.  I simply put a cloth over the cage that protects my basil from the birds and squirrels.  I didn't bother to cover the chard since it seems to do alright in the cold.  It is also protected by a canopy of palo verde branches and a wall on the other side.   

Yesterday, at the Master Gardeners Winter Garden class, I learned that lettuce and carrots thrive in the winter. The teacher recommended that I keep the soil (not the plants) damp. 

While I was at it, I also dug up some basil by the roots and planted them in a pot that I  brought into the house. (The day before I had sent one home with a friend who brought by his extra veggies from Produce on Wheels.) 

A volunteer avocado plant and our basil snug in their pots on the dinning room table.

But I needn't have worried. The basil under the cover fared well in the freeze. I think being in the ground and the nearby tree and wall helped.

I left the cover off to get a little sun this afternoon.  (Oh! That reminds me I should go cover it!) 

We have a tomato plant that still has some tomatoes on it. Looks like it's protected by the warmth from the south-facing wall. 

My curry plants are absolutely thriving in the cold. 

I'm afraid my new dragon fruit isn't doing so well....

I learned that you shouldn't water cactus before a freeze. My bad. 

I also learned from the Master Gardeners class that you shouldn't fertilize the fig tree before the freeze because the new growth would be more vulnerable. I hope that doesn't include the veggie water and used tea leaves. I use to nourish the soil under our little fig tree. We have some nice mycelium in that soil. The instructor did recommend mulch to keep the soil warm. (But keep it two inches from the trunk of the tree.) 

I was happy to hear that I didn't have to water trees that have gone dormant in the winter. 

It's kinda nippy in here.  A nice mug of moringa tea with orange would really hit the spot! 

For the list of upcoming Master Gardeners classes, go to:

https://extension.arizona.edu/pima-master-gardeners