Martha Retallick's Monthly Newsletter | March 17, 2026

The Yellow Issue

The official start of spring is just days away.

So, here's an issue that features one of my favorite seasonal colors.

When it comes to spring flowers in southern Arizona, yellow is right up there at the top of the list. It's bright, loud, and hard to ignore.

Wildflowers? A lot of yellow among them.

But here's my confession:

At my place, nearly all of my attempts to plant wildflower seeds have failed.

The simple truth is, Arizona wildflowers are persnickety about where they wish to set up shop. Being planted here is obviously not to their liking.

Then came the brittlebush.

Shortly after I moved in, I was told that brittlebush just wouldn’t grow in this neighborhood.

That disappointed me because I really wanted to plant some.

A few years ago, I spotted a volunteer seedling in the front yard.

A brittlebush! It simply seeded itself!

In the springtime, this plant is a real show-off with bright yellow flowers. A real photo op for Martha, and yes, I take advantage of it.

After the brittlebush loses its flowers, it just sits there and looks boring.

And, as the weather heats up, it goes into dormancy. Translation: It looks like it’s dead.

But that’s just the nature of Arizona native plants.

They go into dormancy, and it’s easy to just give up on them and pull them out by the roots.

Don’t do that.

Just wait for the rains to return, and you’ll enjoy a brittlebush growth spurt. Come next spring, you’ll be treated to another yellow riot.

Bonus for water harvesters: If brittlebush shows up in your yard, not to worry. It thrives on neglect, and that means you don't have to water it. I sure don't water mine!

Yellow from Down Under

Twenty years ago, when I was in landscape planting mode, a fast grower from Australia caught my eye. I was shopping at a nearby nursery, and I just had to buy some shrubs.

Nowadays, I'm pleased to report that those feathery sennas have taken over my backyard...

Like brittlebush, feathery senna shrubs don't need any supplemental irrigation, and they excel at reseeding themselves.

Take, for example, this new addition to the rock berm at the edge of my cistern's overflow basin...

Before we leave this brightly colored topic, here's an update on a project I covered last month.

Although my initial attempt to brew hard lemonade failed, the second attempt succeeded.

And it's time for a mug, right next to my Meyer lemon tree...

Thank you, greywater-irrigated tree, for providing the lemons for this homebrewing experiment.

A Present for You

Since this issue is coming to you on St. Patrick's Day, here's a present.

To you, my wonderful subscribers, I'm offering a 20% off special on Water Harvesting 101.

Prefer to listen and learn? Water Harvesting 101 is also available as an audiobook.

And now, let's catch up with the Water Harvesting 101 Podcast.

Recent episodes have covered urban wildlife habitat creation...

Creating a Wildlife Habitat Feb 16 · Water Harvesting 101 6:13   ​

An interview with Michael Albanese, author of The Modern Rain Garden: Scrape, Shape, and Plant...

Let’s meet Michael Albanese,... Feb 22 · Water Harvesting 101 10:56   ​

An interview with Michael Groff, host of the Phoenix, Arizona Weather Discussion on YouTube...

Let’s Talk About the Weather... Mar 2 · Water Harvesting 101 13:51   ​

In the coming weeks, I'll be doing interviews with two Tucson-based companies.

You find all Water Harvesting 101 Podcast episodes here and get the transcripts on my blog.

​Kirkus Reviews calls City Nature “A beguiling ramble full of captivatingDIY information and arresting visuals of flora and fauna.” ​ Order the Book

Arizona Colors

Since last month's edition of Arizona Colors got such a wonderful response, it's back!

Let's start with the younger of my two backyard pomegranate trees. Their main water supply comes via my laundry-to-landscape greywater harvesting system...

Thanks to .34" of rain during March 9-10, I was able to capture these droplets on my 8-year-old pomegranate tree...

Both pomegranate trees have fruit buds. The little pome has something extra, two ripening fruits that first appeared last fall...

It's unusual to have ripening pomegranates at this time of the year, but we've had a warm winter.

Speaking of fruit at an odd time of the year, here's the latest news from my Meyer lemon. It's flowering and fruiting at the same time...

Over in the garden, I've been able to harvest a wee bit of broccoli...

And, yellow, seriously. How can we miss you if you don't go away?

For this last image, I need your help.

I've forgotten what this flower is called.

Know what it is? Hit reply and let me know.

As a thank you, I'll send you a signed and numbered copy of my City Nature book.

Questions? Comments? Let's talk! I'm looking forward to hearing from you! ​ Contact me!

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