Sunday, October 4, 2020

Citizen Science: Experimenting with Kitchen Trash to Remediate Soil


I have learned a lot from Master Gardeners - especially their virtual lectures on soil. But to be honest, I have had a few gripes about past presentations where they suggested the use of herbicides to keep out "weeds" or recommended plants that require too much water in our drought-stricken desert.  To their credit, more recent presentations have included rainwater harvesting and permaculture in addition to irrigation systems. So that's good. But there was one statement that really bothered me. The master gardener proclaimed that there was very little organic matter in the desert. I couldn't resist leaving a comment in chat that there could be if we didn't pull all of our native plants and grasses (i.e. "weeds") and left leaves and other debris on the ground to nourish the soil rather than covering everything with gravel. He admitted with a shrug that that was a good idea.   

It is no secret that I am an advocate for returning our yards (as much as possible in an urban environment) back into a native desert habitat.  Dan and I dug up all the plastic and gravel and replaced it with earthwork basins and woodchip mulch in an effort to sink in the rainwater, nourish the soil and grow native and drought-tolerant edible trees. But after 25 years at this location, our yard is still negatively impacted by the weed killers from previous owners.

Scraping out poison green gravel

Even after digging out a layer of green (we believe poisoned) gravel to make a greywater basin for our heritage fig trees, those poor little trees are barely holding on after three years. As an advocate for greywater harvesting, it pains me deeply to admit our failure. And it's not for lack of trying.


I baby those little guys. I get up early to water the organic mulch around the basin (with rainwater when we have it.) I am experimenting with a makeshift "no waste" fertilizer made from kitchen trash that would have otherwise ended up in the landfill or our slow working compost pile. 

I started with a mixture of coffee or tea and crushed organic egg shells - until someone informed me that Tucson dirt already has too much calcium. That made sense since I had dug up some calcium buildup and even some caliche in our yard. (I can still see egg shells in one of the basins since it takes so long to break down...) So now I just use the used coffee grounds and tea leaves...

I also pour all of my vegetable and pasta cooking water in the basin to add minerals. And even the slime water left when preparing nopalitos (prickly pear cactus.) 

After drying my moringa leaves for tea, I put the stems in the basin for mulch. If moringa is good for us, it must be good for the plants too, right? 

I figured banana peels would add potassium.


I read that legumes add nitrogen to the soil, so I started soaking and planting cowpeas and other beans around my fig trees, curry plants and jujubes. The cowpeas actually bloomed under our curry plants and some even grew bean pods. 


But lately the lizards eat the leaves off of the beans. It may be the definition of insanity, but I keep trying.

I heard that hair was good for gardens, so I started adding our pets and even our own hair to the mix. I cut the hair up into tiny bits and mix that with used tea leaves.  I'm not sure it's breaking down to nourish the soil, but at least it's making mulch. 



I've always taken a lot of pics of my process and different experiments in our yard. I like to fancy myself a "citizen scientist."  But since that disturbing statement about our lack of organic matter, I have been really trying to remediate the soil.  

Another comment I heard was that if there is fungus growing in your soil, you are watering it too much. We planted three jujube trees at the same time. I have observed that the jujube tree that is doing the best has little mushrooms growing in the organic mulch around it and clumps of white organic matter. I think that's a good sign.



The other two jujubes have no mushrooms and none of the white stuff and they seem to be struggling. They are less than half the size of the big jujube and much less full. Dan said that those two were planted in the basin where he had dug up oleander shrubs. So the poison from the oleander may still be in the ground there. He also discovered some asphalt along the edge of the basin. First, the weed killer in the green gravel and now this!  Please, keep in mind that what you put in your yard can impact the soil for future owners. 

big jujube in foreground, smaller in background

I finally looked up what kind of ground our jujube preferred to better understand why the one tree was doing better than the others.  I found...

Dig up a bit of soil at the site where you plan to plant or have a jujube growing. Squeeze some in your hand and open your hand again. If it stays in a tight clump that doesn't break up under light pressure, it is clay and you need to steer clear. If it doesn't hold together at all, it is sand and probably doesn't hold enough nutrients. If it breaks up under light pressure, you have loam, and the plant should thrive. When there's a little sand in the loam that's even better for the jujube, which needs a well-drained soil. Make sure you're not at the bottom of a hill or near where your home's downspouts release either because these plants prefer dry feet.

One video I watched had very productive plants growing in red clay soil. According to my copy of Fruits of Warm Climates, sandy loam is the preferred soil type for jujubes, but the plants must be fairly adaptable to do so well there.

Inspired by the screening of "Kiss the Ground" - a doc about how saving our soil could help fight climate change. I decided to do some research on whether my little additions were actually doing anything to remediate the soil. To really know, I would need to get the ground in different areas of our property tested to see if there were any deficiencies. Since that wasn't an option, I did conduct a fascinating google search.

First, I found out there was indeed organic matter in desert soil. To learn more about desert soil, check out this article from the Desert Museum.


But what was my "no waste" fertilizer adding to the soil? Here's what I found out.... Most plants need nitrogen, phosphorus and potassium.

Coffee grounds have a high nitrogen content, along with a few other nutrients plants can use. In compost, they help create organic matter that improves the ability of soil to hold water. We've got a keeper, folks! 

Used tea grounds and fresh tea leaves contain nutrients and tannic acid that, when added to the soil, create a more fertile environment for garden, landscape and container plants. Because tea grounds are natural, organic matter, they increase nutrient levels and improve soil quality as they decompose.

Banana peels contain nutrients that are essential for healthy potted plants. However, they don't contain everything your plant needs. As they decompose, banana peels add potassium as well as small amounts of nitrogen, phosphorus and magnesium to the soil in a similar fashion as a slow-release fertilizer. Not only do they add nitrogen to the soil, balancing any carbon-rich materials that might already be in there, they also add to soil structure and improve drainage.  It adds Tannic acid that slightly lowers soil pH to acid loving plants (best for flowering plants like roses). It also creates good drainage and moisture retention. GONGA! Another keeper! 

Human hair is a rich source of nitrogen. Human hair is good for plants when combined with compost since it takes too long to break down. 

In addition to water and sunlight, plants need certain nutrients to grow, particularly nitrogen. While nitrogen is abundant in the Earth's atmosphere (composing about 78 percent of it), it is in the form of molecular nitrogen (two nitrogen atoms bonded together), which is unusable to plants. For plants to take up nitrogen, it must be "fixed" into compounds such as nitrate (one nitrogen and three oxygen atoms), which plant roots can absorb from the soil.

Were the beans I was planting doing any good? 

While some plants, such as legumes, get their nitrogen through symbiotic relationships with nitrogen-fixing bacteria, others rely on fertilizers, whether organic (composted plant waste or animal manure) or inorganic (the man-made stuff you buy at the gardening center).

https://www.gardenmyths.com/legumes-add-nitrogen-soil/

Legumes, including beans and peas, are able to have a symbiotic relationship with a specific family of bacteria called rhizobia. The plant roots form nodules (little bumps), which house the bacteria. The nodules provide protection for the bacteria and the root provides them with sugars as a food source. In return, the bacteria take atmospheric nitrogen, which plants can’t use, and through a process called nitrogen fixation they convert it to ammonia. The ammonia is converted to nitrate as it is absorbed by the plant.


In a green plant before flowering, 60% of the fixed nitrogen is found above ground in leaves and stem and 40% below ground. The same plant with mature pods has 80% of the plants fixed nitrogen in the seed, 9% in leaves and stem, and remainder in the roots.

Forage crops that are harvested and removed from the land provide almost no nitrogen for future plants because “roots and crowns add little soil nitrogen, compared to the above ground biomass“. About 80% of a plants nitrogen is found above ground.


https://laidbackgardener.blog/2018/09/01/crop-rotation-do-legumes-really-add-nitrogen-to-soil/

The most efficient way of fertilizing soil with legumes is by using them as a green manure. Just as legumes start to bloom, which is when they’ll be richest in nitrogen, work them into the soil where they’ll decompose and release the nitrogen they stored. Don’t let them flower fully and go to seed, as the nitrogen will largely migrate into the seeds. (That’s why legume seeds are high in protein, of which nitrogen is a prime component.) So, with the green mature method, you don’t get to eat your beans and peas or whatever else you sowed: you have to turn the mother plants under.

However, you can have your nitrogen and eat it too, to a certain degree. Grow your peas, beans, broad beans, etc. the way you usually do, harvesting (and eating) their seeds, but don’t pull the plants out in the fall. Instead, cut off the leaves and stems if you want to (although you could work them into the soil as well), but leave the roots in the ground to decompose. Not all the nitrogen moves to the seeds, so the rotting roots still contain a decent share of nitrogen that future vegetables will be able to harvest.

So here's what I learned about the beans I planted. The ones that grew bean pods actually fixed less nitrogen in the soil than the ones with just leaves, so I shouldn't let them flower. Dan disagrees about turning the growth under because it is tilling. He suggested that since I don't want to disturb the microbial growth, that I should just let them rot in the ground to fix the most nitrogen. 

Dan also mentioned that native legumes like mesquite and palo verde fix nitrogen. And they don't require a lot of water and the lizards don't eat the leaves off of them. The green seeds of the palo verde are edible. And the seed pods on the mesquite can be ground into a yummy and nutritious flour. But that's another blog...leave those pods where they land for a natural mulch that doesn't wash away as easily in the monsoon floods (like woodchip mulch can.) Yet another reason to grow native plants in your yard - to leave organic matter for living soil - desert style!  

I don't know about you, but I've learned a lot from my efforts as a "citizen scientist." I will definitely keep using my beneficial "no waste" mulch of coffee, tea, banana peels and hair! While being grateful for our edible forest of native desert plants that don't require so much care to provide us with shade, food and a habitat for critters. 

More information: 

Do Legumes Add Nitrogen to the Soil? -Garden Myths

Recommended by a facebook friend: DIY soil analysis jar

To be continued... 

Thursday, September 24, 2020

What happened to purslane season? (Or coveting my neighbor's purslane)

This year purslane (verdolagas) season was delayed due to the lack of monsoon rains. I was disappointed when we didn't get our usual "alleyway buffet."  But just down the street, I found this fine patch of purslane growing around a palm tree that our neighbor was over-watering. It was the good stuff too! The yummy variety with the tear shaped leaves. 
From previous discussions with our neighbor, I knew it was safe to harvest them since they didn't use any herbicides in their yard and they had given me permission to pick them in the past. 
There were so many! So I pulled a big bunch by the roots so I could plant some in our yard. 

When I got back to the house, I removed the other weeds and grass and placed the purslane roots down in a bowl of water to keep them fresh. 
I used the tender leaves and stems for days in every dish I could think of. Here are a few favorites...

I chopped up a bunch of purslane and I stirred in a tablespoon of pesto. I added some corn for color. Then I spread it on some tomato foccacia and grated some parmesan on top. Baked it for a few minutes for a quick easy dinner.  Yum! 
 

 
 

 


















I had some homemade marinara sauce (that I made from the crate of tomatoes that Produce on Wheels rescued from going to the landfill.) I just added a handful of purslane while I was heating up the sauce for a fast lunch. The purslane made the sauce even more healthy and delicious! 


Meanwhile in our front yard....

It finally rained so we got some round-leafed horse purslane. Unfortunately, this variety is less palatable. It irrigates my throat like raw spinach does. So I have to cook it. While the tear-shaped purslane is tasty raw.


But I had gotten spoiled by all the good purslane in my neighbors yard,  so I went back for more. But this time I gleaned in style with this cute basket! 
To thank them, I went ahead and pulled some undesirable weeds that I knew they didn't want in their yard. It's important to know your neighbor and their preferences. 
Did I mention that I planted some purslane in the basin by our loquat tree? Taking a lesson from volunteers, I planted them around the areas where I water anyway. Say, maybe you've noticed some in your garden bed. Good for you! You can harvest them too! Nothing like free food!
And they grew fine...


Unfortunately, the lizards like it too. They ate every last one of them! (Couldn't get a pic of the little rascals...)

Meanwhile, back in the neighbor's yard...the purslane patch continued to grow - despite having to share it now. What's up, Doc? The neighbor lady said that I could have the ones in front, but leave the rest for the cute little bunny.

There was plenty, so I made more of our favorite purslane dishes. Here I put purslane coated with pesto, tomatoes, olives and mozzarella on some lavash. (Helpful hint: I cook the lavash on one side before adding the toppings and then bake it until the cheese is melted and the lavash is crispy.)
Getting sick of recipes with pesto? Hey! We had pesto left in our fridge! 

OK...Here's a new favorite....A sweet potato and purslane breakfast burrito! 

While I cooked a medium sweet potato in the microwave, I sauteed half an onion. I cut the sweet potato into cubes and browned them with the onions and some purslane. Then I scrambled in three eggs. 

In another pan, I cooked some purslane in tomatillo sauce. The sourness of the tomatillo compliments the citrus flavor of the purslane. (You can also use green chili sauce.)

I wrapped the sweet potato scramble in a flour tortilla and poured the sauce on the top. Then I crumbled some queso fresco on that to temper the sour flavor.  The sweetness of the sweet potato goes surprisingly well with the sour sauce!
Remember how I said that volunteer purslane pops up in the basins where I already water? Well, we FINALLY got some of the good stuff in the basin around our jujube trees! Yeah! 


I try to harvest the purslane while it is still tender, before it gets big and woody. I get it before the little flowers form and it goes to seed. 

If you cut the tops off, it will grow back and give you more to harvest later! 


But we're not the only ones who like them. The lizards and birds prefer the good purslane too.  I watched as this dove walked right past the horse purslane and pecked the seeds off the good stuff.


One time I was picking in the neighbor's yard and the son came out and mentioned that there was purslane growing in his mom's hanging plants. I guess the birds spread them up there!  

A few weeks later I found this on our front porch! Thank you, kind neighbor!  These already had little yellow flowers. I'm hoping birds will help spread them around our yard! 


I did pick a few... 

I washed them over our dish pan to catch the little black seeds. Then I  poured them where I want them to grow in our yard. (In this case, Dan suggested that I pour them into our jujube basin. The roots help make the basin more permeable when it rains. It also decreases erosion in the basin. Working with the wood-chip mulch, it creates a sponge to hold the water longer. How awesome is that!) 


I also tried something new... I had some pickling liquid left, so I put the purslane in there.


I'll let you know how it goes...


For another favorite purslane recipe:

Tuesday, June 30, 2020

Attack Your Water Bill from All Directions!

by guest blogger Steve Barancik

Can you improve your sustainability? We have! At least when it comes to water.


This is our most recent water bill. As you can see, our water usage has been trending sharply down over the last two years. We're now at about 30% of average residential consumption.

We've managed this drop despite:

  • Keeping a garden
  • Keeping chickens
  • Nurturing a couple fruit trees (while giving the death penalty to a couple others)
  • Planting trees and cactus constantly!
It can be done...and you can save money while doing it!
(And remember: lowering your water consumption lowers your sewer bill as well.)

THE STUFF WE'VE DONE

We guttered up part of the roof, where runoff was not being made good use of, and attached the gutters to a tank....



That water now goes toward fruit trees and the garden.

Do we use ollas in that garden?...



Why yes, we do.

We turned off the irrigation to our landscape plants....


You'd be surprised how many of your plants are established and don't need it!


We removed the "weed-control" plastic from both front and back yards....


We used passive water harvesting techniques to:

-redirect (and infiltrate) water where it's needed....


- keep water from jumping the curb and leaving the property....



- and capture water that runs by the property or runs onto the property from neighboring properties!...


We dug a basin and diverted alley runoff to support a mature oak without groundwater....


And by the way, we eat from that oak. So do our chickens!

One key thing we do is make use of our graywater...and here's the thing: We don't HAVE a graywater system; we ARE the system. We capture shower water in buckets....


...and sink water in a dishpan.


(That's Lisa—the other half of "we." She thought of the dishpan as a graywater tool!)

We even catch laundry water in a bucket!...



The tank holds the laundry and spins. The spigot drains the water

Oh, and speaking of buckets...



Why would I go out of my way to get a straight-sided bucket? Well, it certainly makes scooping water out of a flooded street easier! All it takes is a quarter inch rain event for me to be able to fill basins that aren't filling on their own.

I'm a big believer in the water-saving powers of mulch....



I not only try to make use of all the debris and cuttings from plants on my property, but...


I've been known to rescue landfill-bound rakings from neighbors as well!

I even use a technique to irrigate BENEATH my mulch in order to lose less moisture to evaporation.



When it comes to water, I contextualize our use by comparing it with what falls on our 8,257 sq ft lot. At 11.59 in. of rain in a normal year, we have just under 8000 cu. ft. falling on us. Our groundwater use for the last year was only 3300 cu. ft., so I'm pretty happy. I'll be happier still if you're able to put any of these techniques to use yourself!

Another benefit...

This shaded walkway didn’t exist when I moved in six years ago...



Steve is a teacher who thinks his students deserve better than what we're leaving them. You can read more on his facebook page

Saturday, June 13, 2020

Desert Victory Gardens


Inspired by empty grocery shelves and too much free time from sheltering in place, people rushed off to Home Depot to empty the shelves of gardening supplies. Many started their own "victory gardens."

For you young'uns out there…Victory Gardens were made popular during WWII when people planted vegetable gardens to supplement their meager rations. The government promoted victory gardens as a way to support the war effort. They even offered a booklet to help first time gardeners.

I thought a peek at that booklet might be helpful.


1. Don’t start what you can’t finish. Before you start a garden, count the work involved even before seedtime and through to harvest. Abandoned gardens are a waste of seed, fertilizer, tools, insecticides and labor. 

Great advice. Wait! No mention of water? The writers obviously weren’t living in the desert during a 20 year drought and record heat wave!


When I think of Victory Gardens I think of my nana’s garden with perfect rows of vegetables. But nana lived on a farm in the Midwest where there was plenty of water. The gardeners of that age weren’t concerned about pollinators going extinct due to insecticides. They were blissfully unaware of the impact of climate change or fertilizer made out of fossil fuels.



Check out number 7. Don’t let the pole beans block out the beets. In fact, don’t let any of the tall crops shade short ones whatever they are. Growing things must get sun. 

What!? They obviously haven’t watched their veggies wither and die in the scorching June sun. But I’m afraid many first time desert gardeners might.

There are lessons to be learned in the desert all around us.


Baby saguaros survive the harsh summer by sheltering in the shade of native trees like a mesquite or palo verde. They don’t call these trees “nurse plants” for nothin’. Our garden is shaded by two palo verde trees. Veggies grown under mesquite and palo verde trees also benefit from the nitrogen those trees fix in the soil. As far as those pole beans go, the Tohono O'odham demonstrate how the three sisters (beans, squash and corn) benefit from being grown together. The beans climb the corn and squash leaves cover the ground to protect the soil and keep down weeds. 


Unfortunately, the giant eucalyptus tree that used to shade our entire backyard died this year. Now our baby fig trees suffer from direct sunlight. Taking advice from experienced Tucson gardeners, I've concocted shade contraptions out of tomato cages and some recycled shade mesh. No need to shade or water our native trees. Our desert hackberry, acacia, mesquite, and palo verde are thriving this summer with no additional city water. Yeah! The lesson from this is to plant native trees or heritage fruit trees that can take the summer heat!

One of our most helpful low-water gardening methods was inspired by early inhabitants in tune with their desert surroundings.


Back when the Santa Cruz River flowed year around, the Tohono O’odham practiced ak chin irrigation. When the monsoon rains came, the river would overflow washing nourishing silt over the flood plain. The silt would retain the moisture and replenish the soil. It would nourish the durable native seed crops they would plant in the floodplain. In a similar fashion we keep fallen leaves and apply organic wood chip mulch to nourish the soil and retain moisture in our garden and desert landscape. This traditional T.O. method also inspired the rainwater harvesting earthworks method of slow, spread and sink.


NOTE: If it's windy, it's best to water plants in the early morning. Otherwise,  water them after it cools off in the evening so the water won't evaporate in the heat of the day.

Pioneers living through droughts, treated each drop of water as precious. You may have seen westerns where the whole family used the same bath water. Gross! But we can use the same water twice. Dan and I carry our kitchen rinse water out to our hummingbird trumpets. A friend has an outdoor shower that waters his landscape. We use the greywater from our washing machine to irrigate our heritage fig and pomegranate trees.


We gleaned a great water conservation method from the Mexicans who built Tucson. They buried round ollas (unglazed terra cotta clay pots) in the ground and planted veggies around them. Water is poured into the opening on the top. That water slowly seeps through the pot into the soil. The roots of the plants wrap around the olla taking just the amount of water they needed. This saves a lot of water!

Nourishing the soil with compost, covering it with a thin layer of mulch and watering it with rainwater are desert gardening basics. To save water and have a healthy plant or tree, it's important to know how much water they require. Likewise, it's important to sow the right plant in the right season. Another tried and true technique is to plant short-season crops after the monsoons and use added rainwater to grow fast-growing favorites.

Sadly, it’s been a while since it’s rained in our yard. And the rainwater we collected in our water barrels is long gone. So I’ve had to resort to using more city water than I want to this summer. To offset that extra water use, I look for other ways to conserve water. Instead of a full shower, I often take what nana called a “spit bath” or sponge bath and then pour that water onto plants!