The Living Desert

I had to laugh at Bert’s post about how warm it is in Michigan. Two days ago I drove to Vancouver BC from Seattle through a snow storm. Sigh. I’m already wishing I was back in Palm Desert…so today I’ll introduce you to The Living Desert, one of my favorite plant places to visit. It’s got stellar display gardens featuring the vegetation of the southwest desert ecosystems, all labeled, with tidbits of information on natural history, medicinal uses, etc. (American desert purists will need to grit their teeth and endure the exotic animal exhibits, the miniature railroad display, and Village WaTuTu.)

One of these things just doesn’t belong…

But back to the desert display gardens:

Note the sprinkler spray in the background against the sky.  It takes a lot of extra irrigation to maintain this planting density in a desert environment.

And here’s one of my favorite desert natives from last week’s postNolina parryi – on sale in their nursery:

I’m always a sucker for Bad Staking Examples and The Living Desert did not disappoint:

The Living Desert is a mecca for local wildlife, given the plentiful food and water available.  We had company for lunch:

Until next week, I’m in a warm, happy place…at least in my mind.

The winter of our discontent

I was in the field today at our Southwest Michigan Research and Extension Center (SWMREC) so just a quick post and a couple of pictures.  Today is the last official day of winter but you’d never know to look outside. Our current temperature in East Lansing is 78 deg. F.  Our late winter warm up has officially reached historic proportions as we have blown by 1945 as the warmest winter in record in lower Michigan.  To give you an idea of how messed up things are the current temperature in Minneapolis, MN (77 deg.) is 21 deg. warmer than Los Angeles (56 deg.). 

While I hate the be the messenger of doom as Chicagoans enjoy fun and frolic at the beach, for many segments of horticulture what we’re watching unfold is a slow motion disaster.  Phenological development (bud-break, flowering etc.) is currently running almost a full month ahead.  Many important fruit crops such as plums and peaches have started to flower and the rest aren’t far behind.  Based on long-term records it is virtually certain that we will have several hard freezes before the weather warms up for good, meaning that many of these crops will be severely damaged if not destroyed entirely. So, if you’re in the Midwest or East, make the best of the good weather but recognize all good things must come to an end…

Plum crazy.  Plum blossoms at MSU SMREC, March 19, 2012

Just peachy.  Peach tree in bloom. MSU SWMREC, March 19, 2012.

A Good Potting Soil

On this blog we get mad at lots of things.  Sure, anger is fun, but sometimes you’ve got to suck it up and say something nice for a change.  So today I thought I’d point out a product that, while it comes from a company that I’ve had issues with in the past, is, itself, a good product.  I like Miracle-Gro Moisture Control potting mix.  The reason is that it utilizes coconut coir, a waste product from coconuts which holds lots of water and which can still maintain good aeration.  That means a reduced amount of peat.  I also like that the fertility present in this product (so you don’t need to fertilize right after you plant) is 3-1-2 which is appropriate for most situations.  Now, could you mix up you own coir potting mix more cheaply?  Sure, if you can find it.  You could also fertilize with a renewable organic fertilizer.  Still, I think Miracle-Gro got this one right.

Dry doesn’t have to mean dull!

I’m on vacation this week in Palm Desert, California – part of an annual ritual that I’ve enjoyed for about 30 years. Nearly the first thing I do while I’m down here is get away from the golf courses and shopping malls into the high desert mountains. Yesterday my daughter and I hiked Horsethief Creek trail (great name, huh?) in the San Bernardino Wilderness and admired the spring flowers that are just starting to emerge.

One half of my brain was busy noticing all of the native plants that I felt had great ornamental value for home landscapes, while the other half worried about what to do for my blog posting this week. And finally both sides of my brain got together for a chat and here we are with today’s posting.

For many years, the home landscapes down here were primarily of the petunias-and-palms persuasion (or in this case snapdragons and olive trees).

That’s been changing as water has become more limited (i.e., more expensive) and people’s appreciation of native plants has increased. Still, an awful lot of native landscapes rely on traditional desert plants like barrel cacti or agave. They’re pretty – but predictable. And the results are often not natural looking.

So…why not shake things up a bit by using some lesser known, but nonetheless stunning species? While many nurseries might not carry these, the only way to change that is to request them. Savvy nurseries respond to customer requests. Or check with native plant societies, who often have plant sales featuring unusual native species.

Without further ado, here are some great plants from yesterday’s hike, which tolerate low water conditions but have great ornamental and/or functional value.

Arctostaphylos glauca (manzanita) – deceptively tough green leaves against a red-striped bark

The lovely Charlotte displays a good-sized manzanita

Juniperus californica (California juniper) – because every desert landscape needs its own gin mill

Opuntia basilaris (beavertail cactus) – the symmetrical arrangement of tiny spines is aesthetically appealing


Nolina parryi (Parry’s beargrass) – absolutely stunning plant with wickedly sharp leaves

Pentagramma triangularis (goldenback fern) – yes, you can even find ferns in the desert


Astragalus spp. (vetch) – sturdy groundcover with brilliant purple flowers. And it fixes nitrogen!

(A final note: don’t dig these up in the wild and try to transplant them. It’s doubtful they would survive, and in many instances it’s illegal. Do the right thing – support your local native plant nursery and buy them legally.

The Cold Truth

Last week I decided to continue my discussion on cold hardiness and so now, of course, temperatures are forecast in the mid-70’s for this week.  Oh well, I’m still convinced we’ve got one more blast of winter to go and some of this will still matter to someone.

One of the questions posed in response to last week’s post was how much cold hardiness changes during the winter.  Before I get into that, it’s good to review how cold hardiness can be quantified.  Cold hardiness is essentially how much cold a plant can withstand before it suffers damage.  There are two common ways by which this can be measured.  The simplest and most straightforward method is through a whole plant (or whole shoot) freeze test.  In this test, entire plants, usually seedlings, are placed in freezer that is programmed to drop the temperature progressively colder, say from 3 deg C to -36 deg. C

At set intervals, often 3 deg. C, a group of plants are removed.  The plants are allowed to slowly thaw and are then examined for needle damage or bud kill.  At the warmest temperatures, plants are undamaged.  As we examine plants subjected to colder temperatures, we’ll begin to find some with damage.  Eventually we’ll find a temperature where all the plants are damaged.  When we plot the percent of damaged plants versus temperature we can identify an LT50, or lethal threshold where 50% of plants are damaged.

Examples of determining bud damage during whole shoot freeze tests.

The second common assay for cold hardiness is termed Freeze-induced electrolyte leakage or FIEL.  FIEL testing is similar to the whole plant freeze test except that instead of freezing the entire plant or shoot, just a small portion of tissue, such as a conifer needle segment is needed.  The FIEL test is based on the fact that plants can withstand inter-cellular ice (ice between cells) but not intra-cellular ice (ice within cells).  When intra-cellular ice forms it disrupts the cell membranes and cell contents are released into solution.  The amount of leakage of cell contents into solution can be easily measured using a standard conductivity meter.  Again, we can estimate an LT50 by plotting the amount of damage versus exposure temperature.

By assessing cold hardiness periodically through the winter, we can assess changes in hardiness associated with acclimation and de-acclimation processes.  A classic study by Karen Burr and her colleagues demonstrates how quickly acclimation can change.  In their study they tracked cold hardiness of conifer seedlings that we exposed to acclimating conditions (short days and progressively colder temps) and then de-acclimating conditions (longer days and warming temps).  The resulting chart demonstrates how dynamic cold hardiness can be.  When we describe plans based on Hardiness zone we’re talking about their maximum hardiness or the temps they can stand in the mid-winter period.  But note how quickly the lethal temperature rises during de-acclimation.
Seasonal trend in phases of cold hardiness: Acclimation, Maximum hardiness, and De-acclimation

Typically, our most common winter injury problems occur during the de-acclimation phase as temps warm and hardiness is lost.  We saw a dramatic example of this several years ago in western Michigan when an early March warm-up with temperatures in the 50’s F was followed by nights with temps as low a -5 deg.  This resulted in widespread bud-kill in conifer plantations.  With a week of highs in the 60’s and 70’s forecast, it’s easy to see why our current warm-up has everyone nervous.

Maximum and minimum temperatures from a west Michigan weather station

Terry E. for the win!!!

Ray E. was heading in the right direction because he picked up on some family characteristics.

Terry E. got it…

"Blue Ginger (Dichorisandra thyrsiflora).
As per Ray’s offering above, this species is in the same family, Commelinaceae, as the spiderworts, dayflowers, etc."

To any plant i.d. students that may accidentally read this:  family identification is important and helpful. The characteristic triangular flower shape (three petals) and six stamens is a dead giveaway (I get some guff for making them learn families).

Plant photos taken at the Hawaii Tropical Botanical Garden near Hilo.  Lush and gorgeous!

We grow it as a tropical here, but it certainly doesn’t reach 6′ tall as in Hawaii. Easy enough to dig up and overwinter (and share with your friends – we got our clump from local plant goddess Elissa Steeves). 

Quiz (a day early)

Well, I was swamped on my usual posting day, and now I certainly can’t top Jeff”s post – I laughed so hard it took away my initiative.  "Throw and Go" indeed. 

I think we should start our own line of Garden Professors Soil Amendments – "Dr. Holly for Hollies," "Dr. Linda’s Flingable Compost (Not For Tea Dammit)",  and "Dr. Bert’s Conifer Special".  Dr. Jeff would have his own line of slug repellants and traps – available in six-packs. 

Back to my post… you get a quiz!  I’ve rooted through my stockpile o’ photos and found one that just may fool a few of you.  Or not.

 Guess away!