Today I Learned (TIL)

Today I learned that compost isn't a fertilizer, it's a soil amendment. In other words, compost doesn't feed your plants, it feeds your soil. Yes, soil needs food, nom nom nom. Soil is hungry. Soil needs to eat because soil is ALIVE! Good soil, anyway. Somewhere in the back of my head, I knew this. I've heard about soil microbes. But somehow I had it in my head that the compost I work into my garden beds every season was feeding my plants. Although compost does have some nutrient value, its primary purpose is not to provide nutrients to plants -- at least not directly. Compost feeds the soil microbes; in turn, the microbes convert the compost into plant food. Or as Skip Richter, former Texas AgriLife Extension Director for Travis County, says, "Good soil fertilizes itself."


This is how it works: in each teaspoon of soil are millions and millions of microscopic good-guy organisms: bacteria, fungi, algae, protozoa, nematodes (most of which are not disease-causing, but beneficial), and something called Actinomycetes, which are bacteria that have some fungal-like properties. Add it all up, and you can have more than 75 pounds of these critters in 1000 square feet of healthy soil, not counting the critters you can see, like earthworms and pillbugs and ground beetles. Every day, these invisible life forms are hard at work in your soil, doing important jobs like decomposing plant material, fighting disease-causing organisms, breaking down chemicals, and making nutrients available to plants. Soil microbes fix nitrogen, chelate minerals, and produce nitrogen waste, which plants can then take up through their roots.

So what makes soil microbes happy? Carbon-rich organic matter, particularly plant material, green or brown. For example, kitchen scraps. Or composted leaves. Or aged manure, which is what's left after an animal eats, ruminates and eliminates plant matter. Or cover crops, which are planted and turned into the soil before the next season's planting. Organic matter improves the structure of the soil, making soil more permeable to water and air, and improving its ability to maintain pH (a balance between acidity and alkalinity). This creates an environment where soil microbes can thrive and flourish.

Good soil teeming with microbes makes for happy plants. Some soil microbes have a symbiotic relationship with plant roots: the roots secrete stuff that the microbes like, and the microbes create a protective shield around the roots, or convert a particular nutrient to a form the plant can absorb and use. Other microbes break down stuff like leaves and manure and kitchen scraps and grass clippings and insect shells, releasing the nutrients into the soil. Some microbes eat other microbes, keeping checks and balances on the system.

As the foundation of a garden, nothing can replace or make up for lack of good soil. But creating good soil is a process and there are few short cuts. In forests, soil microbes turn layers of decomposing leaves into nutrient-rich humus; rain percolating through the leaf cover acts as a natural "compost tea." A natural, gradual sort of rototilling occurs as the roots of understory plants continually die and regenerate, releasing nutrients into the soil and creating small pockets for air and water to flow through. This process goes on for years, often decades. We can mimic this process by adding compost to our garden beds, mulching with leaves, planting cover crops, keeping tilling to a minimum, and wisely using water, fertilizers and pesticides. But even with good cultural practices, it can take 3 - 5 years to turn poor soil into good soil. So be patient and keep at it.

For more information on soil biology and soil organisms, visit the United States Department of Agriculture's Natural Resources Conservation Service's Soil Biology website.

(Today I Learned features a nugget of information I learned during training to become a Travis County Master Gardener.)


Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.

Today I Learned (TIL)

Today I learned that the term "pesticide" includes a lot of stuff that I didn't know were pesticides. I knew insecticides were pesticides, but there's lots more pests than just insects. Other pests include birds (pests to some people! not me!), fungus, weeds, mites, mollusks (like slugs and snails), nematodes, fish (pests to some people! not me! well, ok, maybe Asian carp), animals and rodents.


So now I have to go take this "Pesticide-Free Zone" sign off my back gate, because I'm a big fat liar. Although I don't use insecticides, I've used fungicides. I've used Sluggo to kill slugs. And yes, I've used glyphosate to try and kill bermuda grass. It didn't work. It killed the green stolons or runners on the top of the soil, but it didn't kill all the rhizomes deep, deep beneath the soil, so it came right back.

Speaking of glyphosate, the other thing I learned is that when stored in galvanized steel containers, glyphosate can explode. Glyphosate reacts with the galvanized steel to form hydrogen gas, which is highly combustible. It's right on the label, in the Directions for Use section. So don't do that!

(Today I Learned features a nugget of information I learned during training to become a Travis County Master Gardener.)

Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.

The fall garden...huh?

No, I'm not crazy, this really is the start of my fall garden. Daytime temperatures remain in the 90's in Central Texas, and my little plot hasn't had measurable rainfall in nearly three months. Since the climate is acting like it's summer, with meteorologists predicting a warm, dry winter (thanks, La Niña!), I decided to plant some heat-loving seeds. And with weekly drip irrigation and daily hand-watering, they've sprouted!

I planted summer squash (this is the 8 Ball variety)


Armenian cucumbers,


and Tiger's Eye bush beans, a new variety from Botanical Interests that were in a Seattle Fling swag bag.


I'll thin the seedlings when each has two sets of real leaves, then mulch around the plants.

The pepper plants I planted in the spring sulked all summer, but two are starting to flower now that temperatures are below 100: this serrano,


and this red bell pepper.


I left a habanero in the ground, too, but it's not doing anything, phooey.

But this Japanese eggplant plant is covered with new blooms.


The Bright Lights chard is still going strong. (After two years, the Fordhook Giant chard is fully worn out; its knarled hearts and roots will be dug out and new seeds planted later this month.)


This spearmint died to the ground in July but came back from the roots with a little drip irrigation.


Now, if we only had a bit of rain and a drop of about five degrees, I'd feel comfortable planting carrots, broccoli, and fall herbs. C'mon, fall! Texas is ready to welcome you with open arms.



Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.

Today I Learned (TIL)

Today I learned how to effectively water a tree.

Although many trees have tap roots, most of an established tree's roots are in the top 6 to 12 inches of soil, and extend out horizontally from the trunk, far beyond its canopy or drip line (the area under its branches). April Rose, Executive Director of TreeFolks, likens the relationship of a tree to its roots as "a wine glass sitting on top of a dinner plate." And despite its name, the root flare on a tree is primarily trunk tissue, not root tissue. Trunks don't take up water; roots do. So watering a tree directly on top of its root flare is a lot less effective than thoroughly watering the soil underneath its full canopy. In fact, keeping the trunk's root flare constantly moist can cause fungal rot.

To keep trees well hydrated in the home landscape during this exceptional drought, water according to age of the tree and the diameter of its trunk in inches. There's a nifty chart on this page from the City of Austin. Baby trees need about 10 gallons per diameter trunk inch every two to four weeks for the first two years. Established trees need fewer gallons per diameter trunk inch (although more gallons overall) and tolerate less frequent watering. Both young and old trees benefit from slow watering methods which allow water to penetrate about 8 inches into the soil under the canopy around the perimeter of the tree. You can use a screwdriver or soil probe to gauge how deeply the water is penetrating the soil; the screwdriver will penetrate easily in moist soil. Mulching under the tree's canopy to a depth of three inches helps hold moisture in the soil and reduces weed growth, but pull the mulch back away from the trunk about 4 inches, to keep the trunk and root flare nice and dry.

For more information on growing healthy trees in Central Texas, visit the TreeFolks resource page.

(Today I Learned features a nugget of information I learned during training to become a Travis County Master Gardener.)

Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.

I am hopeful

This weekend I decided to heck with the drought, the unrelenting heat, and the stage 2 water restrictions. I will have a fall garden. I must. I limited its size to the area I am willing to water with a hand-held hose or watering can, once we go to stage 3 restrictions: one big 4' x 24' bed. And I'm only planting vegetables Jack and I both like, meaning no turnips, no beets, no cabbage, and no Brussels sprouts. Yes, you can just imagine Jack's disappointment.

I spent Saturday pulling up weeds and spring-planted vegetables. It was hard to pull up tomato and cucumber plants that still had green leaves, but they were half-dead and spent-looking. I yanked them out fast, like ripping off a Band-aid. I left the Japanese eggplant and pepper plants, as they still look healthy, and they started to flower last week when the temperatures dropped below 100°F. After weeding and culling, I amended the soil with organic 8-2-4 fertilizer and some cottonseed meal for good measure, added some compost-rich garden soil, and turned the bed. Well, I turned a third of it, before it got too hot to continue. I'll turn the other two-thirds when I'm ready to plant.

It was hot, sweaty work, in 102 degree heat -- again. My instinct says that's much too hot to plant cool-season vegetables. Even though the Aggies say plant now, I'm waiting a few more weeks to plant carrots, dill, garlic, snap peas, lettuce, spinach, and cool-season herbs like cilantro, chervil and dill. I may be forced to plant broccoli before then, only because I imagine the nurseries won't have any transplants in 3 more weeks. But I'd rather wait.

In honor of La Niña's return, I decided to do something crazy. On Sunday, I planted summer squash, cucumbers and bush beans in the third of the bed that I'd turned. I planted varieties that will mature to harvest in 55-60 days, just before Austin typically experiences its first frost. The Aggies say it's getting a bit late for such nonsense, but the meteorologists say it will be a warm, dry winter. I have floating row cover just in case, but something tells me I may not need it.

I'm not sure what to do about wildflowers this year. Without rain, the seeds will need supplemental watering. I'm also not sure what to do about the the front garden in general. I have some ideas for some drought-tolerant additions, but they would all need supplemental watering until they become established, and I won't have the time or money to hand-water both vegetables and shrubs. I need to think about that some more. I have time.

Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.

Today I Learned (TIL)

Texas ash (Fraxinus texensis)

Today I learned that moving firewood kills trees. When people transport firewood from their backyard to, say, a campsite three hours away, they introduce forest pests and diseases from one ecosystem to another. Here's one horrific example of how devastating this seemingly innocuous act can be.

Minnette Marr, Plant Conservationist at the Ladybird Johnson Wildflower Center, says that the Emerald Ash Borer has already wiped out tens of millions of the 8 billion ash trees in the U.S. This lethal pest was first identified in 2002 near Detroit, MI. It likely entered the U.S. in wooden packing crates from Asia, where it is indigenous. The Emerald Ash Borer has already spread to 12 states, and firewood has been implicated in dozens of infestations found in or near campgrounds, including the first infestations in Missouri, Indiana and West Virginia.

As ash trees die, the ecosystems they support are disturbed or destroyed, affecting understory trees, shrubs and wildlife, and providing invasive species the opportunity to invade. The Emerald Ash Borer has not yet reached Texas, but is expected to enter the state within the next decade. When it arrives, our native Texas ash is likely to fully succumb to the pest. Because the Emerald Ash Borer has defied all efforts to eradicate or control it so far, the National Ash Seed Collection Initiative was created in 2005 to collect and preserve ash seed for the purpose of replanting trees once a solution to the Emerald Ash Borer can be found. The Seed Bank at the LBJ Wildflower Center is participating in this project and in the Millennium Seed Bank Project as well.

For more information about the campaign to stop Americans from moving firewood from site to site, visit dontmovefirewood.org. For more information on the National Ash Seed Collection Initiative, visit ashseed.org. And for more information on the Wildflower Center's conservation efforts, visit their Seed Bank page and their Plant Conservation page.

(Today I Learned features a nugget of information I learned during training to become a Travis County Master Gardener.)


Words and photos © 2009-2011 Caroline Homer for "The Shovel-Ready Garden". Unauthorized reproduction is prohibited.