fall vegetable gardening – Extension Master Gardener Volunteers of Durham County

By Gary Crispell, NC State Extension Master Gardener ^SM volunteer of Durham County

Summer must have started because Memorial Day has come and gone. Today is July-like — humid, rather warm, and breezy. (This informational tome of wisdom and snarkiness is still human generated, which means a deadline exists prior to the first of the month — hence the less-than-timely observation.) It is threatening to rain, but the credibility of the threat is nonexistent.

Meanwhile the Accidental Cottage Garden (ACG) is trying its best to discern exactly what season it is and what it should do about it. Current cohabitating contributors to the conspicuously colorful collection of organisms with cellulose cell walls include lance-leaf coreopsis (Coreopsis lanceolata), orange daylilies (Hemerocallis lilioasphodelus), black-eyed Susans (Rudbeckia hirta), Stokes’ aster (Stokesia laevis), wand flower (Oenothera lindheimeri, formerly known as Gaura lindheimeri), gaillardia (Gaillardia pulchella), Asiatic lily (Lilium x ‘Corsica’), thyme (Thymus vulgaris), and prairie coneflower/Mexican hat (Ratibida columnifera). The English daisies (Bellis perennis), flax (Linum usitatissimum), larkspur (Delphinium carolinianum), and sweet William (Dianthus barbatus ‘Sweet Black Cherry’) are carry-overs from last month.

Close-up of white flowers with clustered petals surrounded by green leaves.

A cluster of vibrant yellow flowers with dark brown centers, commonly known as Black-eyed Susans, blooming in a garden.

Left to right: New Jersey tea (Ceanothus americanus) (Image credit Debbie Roos CC BY 2.0); black-eyed Susans (Rudbeckia hirta), Stokes’ aster (Stokesia laevis), (Image credits Gary Crispell),

Others new to the conspicuously colorful collection are New Jersey tea (Ceanothus americanus), butterfly weed (Asclepias tuberosa), purple coneflower (Echinacea purpurea), butterfly bush (Buddleja davidii), and love-in-the-mist (Nigella damascena – a total surprise hidden amongst the larkspur). A decidedly delightful display, if I do say so myself.

The weather continues to be perplexing. Do we garden in jeans or shorts — sweatshirt, tee shirt, or layered? Too many decisions.

Thought for the month: If a beverage containing alcohol is a potent potable, is a non-alcoholic beverage impotent? LET’S GARDEN!!!

Lawn Care

Because I realize there are some of you out there who are too busy/new to the Piedmont of NC/not paying attention/just plain horticulturally uneducated, I am urging you to fertilize your warm-season grasses (Bermuda, zoysia) now, as in right now. April or May would have been just fine, but now it is mandatory. You will know how much and what formulation because you got a FREE SOIL TEST earlier. (No. Probably not, as you have not fertilized yet. All excuses from above, I suppose.) Remember that soil tests are free from April through November. Contact the NC Cooperative Extension office at 919-560-0525 for more information on obtaining a free soil test kit with instructions. If you insist on winging it, 1 pound of nitrogen per 1,000 square feet of turf is a safe application rate.

Extension Horticulture Agent Jeana Myers from NC State Extension demonstrates how to collect a soil test. (Video credit: Homegrown YouTube Channel from NC State Extension).

June is THE month to fertilize centipede grass. The 1 pound per 1,000 sq. ft. rate applies to centipede as well.

Summer is a good time to core aerate¹ any lawn. Aeration facilitates air, water, and nutrient movement through the soil and to the root zone.

Always wanted a zoysia grass lawn? June is a really good month to start one. You will need to use sod or plugs, as zoysia seeds are not commercially available.

Fertilizing

Dogwoods (Cornus spp.) can be fertilized now. Again, a FREE SOIL TEST and its resulting recommendations would be helpful here — too many variables for general guidance.

Throw a handful of 10-10-10 or equivalent at the plants in the veggie garden. It will assist the quantity and quality of your anticipated harvest.

Planting

All of y’all who have been waiting for warm weather to plant your vegetable garden better hustle up now. It is here and gone and come again. So, if you want tomatoes before Labor Day… At this point it is necessary to install plants rather than seeds for most vegetables other than beans and maybe pumpkins.

For those of you who plan ahead, it is time to start seeds for your fall/winter garden. Cruciferous veggies (cabbage, broccoli, cauliflower, kale, collards) can be started now to be transplanted in mid-July. For more information on fall vegetable gardening read more about year round gardening on our blog.

Pruning

Coniferous² evergreens such as pine, juniper, chamaecyparis (Chamaecyparis spp.), and cryptomeria (Cryptomeria japonica) can be lightly pruned now. Be aware that they generally do not produce new foliage beneath a pruning cut.

Hedges and any severely overgrown plants can be radically cut back. The book says never more than one-third of the top, but anecdotally I can tell you that many broadleaf evergreens and deciduous shrubs can be reduced to 18 inches or so and recover nicely. (The author, the publication, the Extension Master Gardener ^SMprogram, NC State Cooperative Extension, and the university assume no liability for plants that do not recover.)

Continue to pinch back garden mums (Chrysanthemum × morifolium) until mid-July if it is fall blooms you desire. If you do not care when they bloom, well, good for you, you rebel.

Bigleaf hydrangea (Hydrangea macrophylla) can be pruned as soon as the blooms fade.

Azaleas, including Encore® cultivars, can be pruned anytime from bloom fade through the 4th of July.

A dense rhododendron shrub with many green leaves and some branches with brown drooping leaves caused by dieback.

Rhododendron dieback from Botryosphaeria dothidea (Image credit: Elizabeth Bush, Virginia Polytechnic Institute and State University, Bugwood.org)

Dieback can occur in ericaceous³ plants in early summer. Rhododendrons, including azaleas, pieris (Pieris spp.), and others can be infected by the fungus Botryosphaeria dothidea or a Phomopsis spp. fungus. Scraping away the bark with a knife reveals a reddish-brown discoloration under the bark on dying branches of rhododendron. On azaleas, the discolored wood under the bark appears chocolate brown. Prune infected branches well below the point of infection and sterilize your pruning tools between cuts with a 10% bleach solution or 70% isopropyl alcohol. (Good gracious, NO — not the 140-proof vodka.) Destroy all clippings.

Spraying

Be on the lookout for the following dastardly destructive six- and eight-legged pests: lace bugs (azaleas, pyracantha), leaf miners (boxwoods), spider mites (needle-leaf evergreens), bagworms (mostly, but not exclusively, on needle-leaf evergreens), and aphids on anything they can get their pointy little mouthparts into.

There are numerous pest-control products available. Try organic products first. The planet is counting on you.

Close-up of a green beetle resting on a leaf, displaying iridescent colors and intricate markings.

Three green and brown beetles resting on a damaged green leaf with visible holes and erosion.

Japanese beetle adult and leaf damage (Image credit: Steve Schoof, NCSU)

June is prime Japanese beetle time. (Contrary to popular myth, they do not sing “Sgt. Pepper’s Lonely Hearts Club Band” in Japanese while devouring your roses and crape myrtles.) Treat them with an appropriate pesticide or pick them off and drown them. Smush them if it gives you satisfaction. (Personally, “I Can’t Get No Satisfaction.”) You will find additional help in this previous blog post – Coping During Japanese Beetle “Season.”

Be aware of tomato early blight. It shows up as brown spots on the lower leaves, followed by yellowing around the spots; eventually the whole leaf will usually turn yellow and drop. There are several products available to treat early blight, some with a zero-days-to-harvest rating.

Vegetable gardens are susceptible to a myriad of pests. Lots of insects (and other genera) like the fruits of your labor as much as you do — and they outnumber us. There are multiple species of worms seeking sustenance from your cruciferous veggies. Then there are the cucurbit lovers: cucumber beetles on (believe it or not) cucumbers and other cucurbits, squash borers on most squash varieties and melons. You might also find flea beetles (they do not sing either) on any bean species, plus tomatoes and eggplant. And let us not forget the ubiquitous aphids.

Continue spray programs for roses, fruit trees, and bunch grapes.

Use pesticides only when necessary. ALWAYS read the label and follow the instructions. Try organic first.

Miscellaneous Stuff to Do Outside in June

A word about watering. Sometime this summer you will find it necessary to supplement Mother Nature’s somewhat capricious watering schedule. Plants, including lawn grasses, need about one inch of water per week to sustain growth. It is best applied in the early morning to minimize evaporative loss. Evening watering is acceptable if leaf surfaces will be dry before nightfall — damp leaves promote disease. More information on drought-related watering is available in this previous blog post.

Alas, strawberry season is over. It is appropriate now to renovate those beds in preparation for September planting.

Once you have exhausted the day’s to-do list (and most likely yourself), take time to kick back and enjoy the garden. Outdoor living spaces were made for June evenings — food, family, friends, firepit, and a cool beverage (to go with the s’mores, silly). That is what it is all about. As T.S. Eliot wrote in “Choruses from “The Rock” (1934): “There is no life that is not in community.” Find your community and welcome summer.

Notes

1-Core aeration is the mechanical removal of small plugs of soil and thatch from a lawn, improving air, water, and nutrient penetration to grass roots.

2-Coniferous refers to cone-bearing evergreen trees and shrubs, such as pines, junipers, and firs.

3-Ericaceous refers to plants in or adapted to the conditions preferred by the heath family (Ericaceae), which thrive in acidic soils. Rhododendrons, azaleas, blueberries, and pieris are common examples.

Resources and Additional Information

A how-to on preparing your (free until November!) soil test: Now’s the Perfect Time to Test Your Soil! – Durham County Center | N.C. Cooperative Extension

Helpful information on summer and fall vegetable gardening: Vegetable Gardening 101 – Gardening | NC State Extension and previous blog post Garden Veggies Year Round – One Gardener’s Calendar

More about rhododendron and azalea dieback and other diseases: Azalea & Rhododendron Diseases in South Carolina: Identification, Prevention, and Treatment | Home & Garden Information Center

Learn more about Japanese beetle management here: Japanese Beetle | NC State Extension Publications and previous blog post Coping During Japanese Beetle “Season”

Guidance for drought-related watering strategies: Essential Gardening Tips for Drought Conditions

Edited by Susan Sharp, NC State Extension Master Gardener ^SM volunteer of Durham County

Article Short Link: https://wp.me/p2nIr1-7BO

By Melinda Heigel, NC State Extension Master Gardener^SMvolunteer of Durham County

(Left) The big, bold leaves of ‘Red Giant‘ mustard take center stage in this large container providing texture, height, volume, and intense color. This mustard was fast growing, survived cold temperatures with minimal protection. It was also slow to bolt when the weather got warm in the spring. (Middle and right) The ‘Miz America’ mizuna-mustard hybrid was equally stunning in a built-in planter box and potted alongside pansies, violas, and a lemon cypress, (Hesperocyparis macrocarpa ‘Goldcrest’ ). While these head turners are edible, I planted them for their color and form. (Image credit: Melinda Heigel)¹

Wait? I thought this was a blog about gardening, not cooking! Well, the mustard I am referring to isn’t the zippy condiment we all know but is the plant I discovered is a star in fall containers. I’ve written in the past about the herb bloody dock, also known as sorrel, and what a bullet-proof companion it is for pansies, violas, snapdragons, ornamental kale, cabbage, and other autumn-to-spring plants. Last year I tried adding mustard to my potted arrangements and was thrilled with the results.

A Question of Hardiness

Along with broccoli, collards, and kale, mustard is a cole crop that performs best in consistently cool temperatures when grown in the vegetable garden. But over the last couple of years I’ve started seeing different mustard plants at the local nurseries more and more alongside the annual cold-weather ornamentals. The mustard plants offered some really interesting leafy forms for planting in pots. I was dubious, though, about their hardiness over the winter, unprotected in containers, but what is gardening without experimentation? With the exception of a couple nights with temps in the teens in the dead of winter, I did not cover any mustard plants. To my surprise, they performed just as well as their cool-weather container companions.

(Left to right) Mustard plants already making a debut at the local nursery this month alongside fall’s usual suspects. In late spring of 2024, my ‘Miz America’ mustard plants produced bright yellow flowers when they bolted. The plants really earned their keep–providing interesting leaves for months followed by these showy late-spring blooms. And did I mention spring pollinators were drawn to their nectar and pollen? (Image credit: Melinda Heigel)

If the spring weather warmed up too quickly, as it is known to do in central NC, I also wondered whether these cool-temp lovers would bolt (flower) and fade too quickly given their prominent placements. Most of the containers were in the hottest place around our house–on a dark-colored deck that receives full sun. Happily, the mustard tolerated a good number of hot days in late April and early May before bolting. Even after flowering, they were still going strong when I removed them to make way for summer plants. While I may have just the right conditions in my landscape for these results, I can’t chalk this success up to anything remarkable. Mustard plants are easy to grow. And I’ve come to find out, one of the types I planted is actually bred to be bolt resistant, ensuring longevity.

Mustard Varieties for Annual Container Gardening

Red Giant Mustard (Brassica juncea ‘Red Giant’)

I found this to be a striking specimen. In my big container, it quickly grew to be over 3 feet tall, with gracefully arching leaves that reminded me of a classical acanthus—yes, you really can wax poetic about mustard. If grown in optimum conditions, this plant has been reported to grow as large as 4 feet. Though I have not experienced this, don’t underestimate its vigor. When planning your mixed pot, give it plenty of room. ‘Big Giant’ mustard leaves start off green but mature into a deep maroon with contrasting green stems, midribs, and leaf veins. This plant is specifically bred to be both cold-and-bolt tolerant. Frost intensifies the color. It grows best in full sun with well-drained soil. It paired nicely with the flowering cushion spurge ‘Ascot Rainbow’ (Euphorbia x martinii ‘Ascot Rainbow’) as a backdrop.

In terms of its characteristics as an edible, this mustard has a bold taste like wasabi or horseradish and can be pickled, eaten cooked (mature leaves), and eaten raw (young leaves). Hot weather sharpens the flavor, especially in the older leaves of the plant.

Image credit: Melinda Heigel

Miz America Hybrid (Brassica juncea ‘Miz America’)

At once striking and delicate, the deeply lobed and serrated leaves of this mustard are a showy deep burgundy with vibrant hot-pink midribs and venation. Like ‘Red Giant,’ it is a fast grower and prefers full sun. It serves as an excellent filler in containers, given its upright and compact habit.

From a culinary perspective, ‘Miz America’ has a mild peppery flavor. It’s a hybrid plant that comes from crossing two distinct mustard varieties. One of the parents, mizuna, is a mild green mustard, which gives ‘Miz America’ its beautiful serrated edges and mild flavor. You can enjoy the leaves of all mustards in a salad by picking them young—under 6 inches. If picked at a more mature size, they can be added to a dish to impart a hint of sweetness with a mustard tang. Consider adding them to a bowl of hot, creamy soup such as butternut squash or tomato. Not only does it give you additional nutritional value without adding additional calories, but it adds a nice crunch and a bit of zing.

I’ve yet to replant my containers and built-in planter box this fall, but you’d better bet that mustard plants will be making a repeat performance in 2024. I’ve already seen ‘Red Giant’ in the nurseries, but I am also on the hunt for some other intriguing mustards to test out—namely ‘Brazen Brass’ and ‘Dragon Tongue.’ If you want something unusual, showy, and even tasty in your fall plantings, remember to go heavy on the mustard.

Notes

1–Want a closer look at a photo? Simply double click on the image for a better view.

2–According to Missouri Botanical Garden, Brassica juncea, known by its common names Chinese mustard or brown mustard, is listed as a noxious weed in some states including Michigan, Florida, and Alaska and considered invasive. Cultivars discussed here are bred to be used as annual edibles or ornamentals in gardens.

Resources and Additional Information

Learn about growing cole crops in central NC: https://pender.ces.ncsu.edu/2021/09/plant-cole-crops-now-2/
More on vegetable gardening during cool seasons from our blog: https://durhammastergardeners.com/2022/09/14/garden-veggies-year-round-one-gardeners-calendar/
More ideas on fall flowers and veggies for winter color: https://pender.ces.ncsu.edu/2020/10/plant-flowers-and-veggies-for-winter-color/

Article Short Link: https://wp.me/p2nIr1-54k

Extension Master Gardener Volunteers of Durham County

Category: fall vegetable gardening

To Do in the Garden: June 2026