To Do in the Garden: October 2024

By Gary Crispell, NC State Extension Master GardenerSM volunteer of Durham County

While the Accidental Cottage Garden (ACG) took a hit from all the rain, the blooms of the zinnia (Z. elegans) and gaillarda (G. pulchella) still delight with punches of color. Scene from the late-season and very soggy ACG. (Image credit: Melinda Heigel and Gary Crispell)

And suddenly it’s October. When and how did that happen? Although, I’m pretty sure I got here by boat. Hopefully, the three-month monsoon season is over, but we could still get another gift from the tropics. (Someone needs to do something about the butterflies in West Africa.) 

The rain gauge indicated 12 inches for September. The last time I remember anywhere near that amount was in 1996, when our dear, yet very angry friend, Fran, visited for a harrowing overnight stay. 

The Accidental Cottage Garden is bowed but not broken. Everything is beaten down and bent over. Kinda looks like myriad ground covers gone berserk. However, in the tangles, one can find an assortment of delightful blooms. Zinnias (Z. elegans), African marigolds (Tagetes erecta), mock vervain (Glandularia bipinnatifida), plucky gaillardia (G. pulchella), evening primrose (Oenothera lamarckiana), Autumn Joy sedum (S. ‘Herbstfreude’), hardy ageratum (Conoclinium coelestinum), and two volunteer cosmos (C. bipinnata) are doing their best to overcome the odds and keep the neighbors smiling. 

So, what’s going on in your garden? Perhaps you’ll find something useful or amusing (or amusingly useful) in here this month (or not). Either way, let’s garden. 

LAWN CARE

Attempt to prevent leaf accumulation on lawns, especially newly seeded or overseeded ones. And be sure those receive adequate moisture. (Yeah, I know. Really?!?) About those leaves, please compost them or put them into a natural area. They do not belong in the landfill. Continue mowing cool-season grasses (tall fescue, bluegrass, perennial rye) at 3 ½” to 4.”

FERTILIZING

Not much to see (or do) here, folks. Drop some fertilizer on the spring-flowering bulb beds. 10-10-10 or equivalent will do just fine. Work it into the soil where possible. Store any leftover fertilizer in sealed containers in a dry location until next season. 

PLANTING

(Left to right) Pansies brighten up the shorter autumn days. Tulip and pansy pot planted in the fall. The pansies were joyous for 3 long seasons: fall, winter, as well as in the spring when the tulips also came into their own. (Image credit: Melinda Heigel and Marcia Kirinus)

“FALL IS FOR PLANTING,” repeated…again. Things planted now will have most of the winter to put down roots and get established so they’ll be ready for another Sonoran June. Consider planting a cover crop on any part of the veggie garden not growing a fall crop. Crimson clover (Trifolium incarnatum) or winter rye (Secale cereale) will keep the soil intact and add nutrients to it.

Plant spring-flowering bulbs (tulips, daffodils, narcissus, etc.) this month. Plant salad greens and short-season root crops (carrots, radishes) in a cold frame. Do something nice for yourself and plant pansies. A pot full of their smiling faces can do a lot to lift the gloom of a day when it’s 34 degrees and raining. Caveat: deer LOVE them.

PRUNING

Wait until it gets cold (post-killing frost) and intends to remain that way for a bit. The goal is to avoid any new growth attempting an emergence until spring. Cutting back everything in the perennial garden is something your grandmother did but is no longer considered “best practices.” Apparently, there are solitary native bees that lay eggs on or overwinter in the stems of said perennials. Your grandmother didn’t tell you because she didn’t know. Somebody with a great deal of intellect, curiosity, and, quite frankly, an amazing amount of time on their hands figured this out in the not-too-distant past (post-grandma period). So, DON’T cut back your perennials unless the HOA is fixin’ to put a lien on your house. Chances are an HOA wouldn’t let you plant perennials (aka, weeds) in your yard to begin with. They—the stems, not the HOA—are better left until spring. Root prune any trees or shrubs you plan on moving in the spring. Have you noticed that most of fall is spent preparing for spring? That’s what the plant kingdom does. Those of us in the animal world get ready for winter. Plants have their eyes on the future. 

Close up of the rattlesnake master (Eryngium yuccifolium), an example of a hollow-stemmed plant that provides valuable over-winter habitat for nesting insects. This photo shows the stems after cutting in the spring once insects may have emerged. Other plants with hollow stems include anise hyssop, bluestar, milkweed, tall tickseed, and pink muhly grass, among others. Pithy-stemmed plants like purple coneflower (Echinacea purpurea) provide habitat for some bees who use pith to build their nests. (Image credit: Debbie Roos)

SPRAYING

Most of the pesky little &*@$# have gone to sleep for the winter. There are two notable exceptions: lace bugs on azaleas (especially those in full or mostly sun) and scale on euonymus and camellias. Both can be treated with horticultural oil. It smothers the adults and their eggs. 

Damage caused by azalea lace bug, Stephanitis pyrioides (Scott). (Image credit: James. L. Castner, University of Florida)

PROPAGATION

Some of you are starting plants from cuttings. Maybe even in a cold frame that doesn’t have veggies planted in it. Be sure to monitor it at least bi-weekly for health and vigor. Water as necessary. 

Other amazingly fun stuff to fill whatever “perfect October days” we may be granted by whomever is in charge of such things:

Take soil samples while they are FREE through November. Sample collection boxes and instructions are available from the Durham County Extension office at 721 Foster St. or from the NCDOACS.

Repeating: compost any leaves you gather up. Sending them to the landfill is a definite no-no.

Cleanse the bird feeder(s), fill ‘em up, and put ‘em out. Sit back and watch. It’s therapeutic.

Prepare all your lawn and garden equipment for its long winter’s nap.

if you band your trees to mitigate the number of insect larvae that might feed on your trees in the summer (and whose digestive tracts are highly inefficient, causing copious quantities of worm feces to accumulate on whatever is under said trees—a friend told me about this), now is the time to do this (if you remember what “this” is after the mid-paragraph digression).

Sticky bands capture female moths who will begin crawling up tree trunks in the fall to mate and lay eggs that will hatch into the small caterpillars we call Cankerworms. In the spring, these hungry caterpillars emerge and eat the leaves of hardwood trees in urban areas and can be a threat to tree health and mortality. Some experts recommend waiting until all the leaves have fallen before banding. (Image credit: William A. Carothers, USDA Forest Service, Bugwood.org.)

For a glimpse of spring in the bleak midwinter, try forcing spring-flowering bulbs. Daffodils and narcissus are good candidates for this exercise. Plant the bulbs in pots early in October and put them in the refrigerator. This assumes that you have a huge refrigerator and no teenagers in the house. In 12 weeks (Happy New Year!), remove them and set them in a sunny window where you can watch them grow and bloom. Fun! Kids get a kick out of it.

Paperwhite narcissus bulbs forced for indoor bloom. (Image credit: University of Florida/IFAS Extension and Cornell Cooperative Extension)

Bask in the beauty of the season when the leaves show off their true colors without the chlorophyll mask they have worn all summer. We may have to do that close to home this year. The mountains are closed until further notice. Sad. It’s the beginning of fire pit season. ‘Nuff said. Enjoy it, y’all! 

Resources and Additional Information

Article Short Link: https://wp.me/p2nIr1-558

A Better Way to Think About Soil

By Peter Gilmer, NC State Extension Master GardenerSM volunteer of Durham County

(Image credit: Pixabay)

Spring is coming, and the soil temperature is rising. Soon enough, it will be time to direct seed and to transplant the garden. Is my soil ready? What should I do to get it ready? Do I need a new soil test?

Many of us know that a soil test can be helpful, particularly when it comes to pH and lawn care. The usual soil test results recommend adding nitrogen, plus or minus phosphorus (P) and potassium (K). My results have always shown a reasonable pH, P and K values in the normal range, and the default recommendation to add nitrogen (N). As you may know, nitrogen is not actually measured. Is this enough to care for my soil?

Microbial Role in Soil Health

There is a way to build better soil, and it requires thinking about how soil works. These ideas come from the growing movement sometimes called regenerative agriculture. The basic ideas are simple, ideas that many of us sort of know. Soil function depends on microbial life, and the key to strong soil performance lays in promoting a healthy biome. Although there are other important players, we will focus on bacteria and fungi.

It turns out that these tiny organisms feed the plants by providing what the plant needs in the form that the plant requires for uptake. The essential nutrients, including nitrogen, phosphorus, and potassium (along with others) are already in the soil in nearly inexhaustible amounts, but are either remote from the plant’s reach or not in a plant-available form. The microbes are able to reach far beyond the root tips and can process the nutrients into plant-available form for uptake by the roots. There is no need for us to put the nutrients there when the microbiome is healthy. There are exceptions to this rule to be mentioned later. There is need to promote the microbial life central to soil health.

The Plant-Microbial Relationship

Before we get to the “how to” regarding microbial health, let’s review the role the plant is playing in getting its nutrient needs met. The plant is the energy source (food) for the bacteria and fungi in the soil. In other words, it is the plant that feeds the microbiome. This food is in the form of carbohydrates (sugars) produced by the plant via photosynthesis. It is estimated that 30% of the carbohydrates produced in the plant leaf are given to the microbiome. This ancient, essential relationship between soil, microbes, and plant has evolved over millions of years. Our job is to promote this functionality. It is not our job to provide nutrients directly. They are already there, in abundance.

How To Support Soil Microbes

Minimize Soil Disturbance

How do we support the microbes? The ideas are simple and basic for most gardeners. First, we need to minimize disturbance. This means less tilling. Why? Because tillage disrupts the microbial-plant dance that makes it all work. Soil aggregates, those tiny bundles of soil packaged with the help of microbes, are destroyed, and the ability of soil to hold onto water reduced drastically. The rhizosphere, the micro environment where fungi, bacteria, and root cellular membranes make critical exchanges, is disrupted physically in the process of tillage. So, step one, reduce disturbance.

The area of soil surrounding the plant root, the rhizosphere, is teeming with microbial activity. (Image credit: NC State Extension)

Of course, when planting anything, there will be disturbance. When I put a transplant into the ground, I dig (disturb) an appropriate-sized hole. What I do not do is turn over (till) the entire bed. Initially, tillage is useful in establishing a bed in an area that historically was lawn but is not used annually to clear the bed of weeds. Tillage disrupts the microbiome and doesn’t control the weed either.

Cover the Soil

Second, we should always cover the soil, either with living plants or with materials derived from dead plants (mulch). Exposed soil does not do well with direct sunlight, falling rain, and wind. In the garden, coverage is best done with cover crops in between planting seasons and wood chips or mulch where the paths are located. In a planting bed, coverage might consist of a perennial ground cover that not only covers the soil between plantings, but also puts another living root into the soil. Large areas of mulch in a planting bed might initially look good, but over time will get weedy, and the mulch cover does not provide a living root to feed the microbes.

Planting beds flush with cover crops consisting of radish, crimson clover, and rye, with wood chips covering the walking paths. (Image credit: Peter Gilmer)

In terms of cover crops, there is much that goes into the decision as to what cover crops to use. There are warm season covers (like buckseed) and cool season options (like crimson clover). There is the need to terminate the cover crop when the time is right to plant the main crop. This might involve mowing followed by a silage tarp. There are cover crops that winter kills. Terminating the crop before it goes to seed is critical. Polyculture, meaning multiple types sown at the same time, is better than a mass planting of a single crop. A full discussion of cover cropping goes beyond the scope of this article.

Acting as a living mulch, crimson clover is interplanted with cool weather vegetables. This cover crop provides weed suppression, erosion control, and maximizes the number of living roots in the soil–all while adding to the nitrogen pool through nitrogen fixation. (Image credit: NC State Extension)

Maintain Living Roots

Third, we should keep a living root in the soil as much of the time as possible. Remember, it is the plant through its roots that is feeding the microbiome and getting essential nutrients in exchange. The plant heals the soil. Remember when a field in fallow was considered good, a way to let the soil rest? All along the soil really needed living roots pumping fuel (carbon) to the microbiome. Planting something in between the main crop is an effective way of getting more roots in the soil. For example, you may have heard of marigolds being planted in between tomato plants.

Choose Diversity in Planting

Fourth, we should diversify whenever possible. Plants are not all the same, and they have unique relationships with their microbial partners. Monocultures are not nearly as healthy and resilient as polycultures.

Encourage Regenerative Animal Grazing

Finally, specifically in the world of farming, grazing animals can play a major role in restoring soil health. We cannot delve into this fascinating relationship in this article, but grazing animals (think bison) have played a major role for millions of years in keeping soil healthy. While this might not be applicable to the home gardener and not something I do myself, grazing is a powerful tool in managing and improving soil health.

To summarize, what should I, the home gardener, do to ensure healthy soil in my garden?

  • Minimize tillage
  • Keep soil covered
  • Keep living roots in the soil
  • Diversify plant life

I did mention that there are exceptions to these rules, and one that I should highlight is lawn maintenance. We have learned that lawns are poor supporters of the greater ecosystem. They are generally monocultures with superficial root systems, and do not develop healthy microbial life. Lawns are therefore more dependent on fertilizers and irrigation systems, all the more reason to reduce their size whenever possible.

Below you’ll find some of the best resources that I have encountered on the topic of soil health. I encourage you to dive deeper into this fascinating world.

  • Brown, Gabe.  “Dirt to Soil.  One Family’s Journey into Regenerative Agriculture. “ Chelsea Greensboro Publishing.  2018.  This is a fascinating story, well told, of going from frequent tillage and fertilizer to cover crops and soil carbon capture.
  • Frost, Jesse. “The Living Soil Handbook.” Chelsea Green Publishing. 2021. This is a great how to reference book for vegetable farming.
  • Lowenfels, Jeff and Lewis, Wayne. “Teaming with Microbes.”  Timber Press.  2010.  This is where my journey of discovery began.  It was given to me by a fellow Master GardenerSM volunteer.
  • Lowenfels, Jeff. “Teaming with Fungi.” Timber Press. 2017. I knew next to nothing about fungi, and this book introduced me to these critical microbes who are critical to many basic life functions on this planet.
  • Lowenfels, Jeff. “Teaming with Bacteria.” Timber Press. 2022. If you want to know more about the rhizosphere, this is the book for you. What an incredible relationship between microbe and plant root.
  • O’Hara, Bryan. “No-Till Intensive Vegetable Culture: Pesticide- free methods for restoring soil and growing nutrient-rich, high-yielding crops.” Chelsea Green Publishing. 2020. This guy is the master at growing vegetables and knowing what inputs (homemade compost teas) are needed and when.
  • Still, Jon. “A Soil Owner’s Manual.” 2016. A 75-page, concise overview of soil management that you will likely read more than once.

Happy gardening this spring. Go microbes!

____________________________________________________________________

Resources and Additional Online Information

Learn more about soil testing with NC Cooperative Extension’s handy online guide chock-full of resources.

https://durham.ces.ncsu.edu/2020/05/nows-the-perfect-time-to-test-your-soil

For a detailed look online about the benefits of no-fill farming, check out resources by Penn State University, North Carolina State University, and Cornell University.

https://extension.psu.edu/no-till-farming-and-healthy-soils-work-hand-in-hand

https://plants.ces.ncsu.edu/garden_detail/vegetable-no-till-garden

Planting cover crops is an excellent way to maintain soil health, suppress competition from unwanted plants like weeds, and stem erosion. See NC State Extension and Clemson Cooperative Extension’s online sites about how to use these plants in traditional agriculture and in raised beds.

https://growingsmallfarms.ces.ncsu.edu/growingsmallfarms-covcroplinks

https://caldwell.ces.ncsu.edu/2022/07/try-cover-cropping-a-guide-for-home-gardeners

Article Short Link https://wp.me/p2nIr1-4hE