July: To Do in the Garden

by Gary Crispell, EMGV

Alright, y’all. It’s July. This is the Piedmont of North Carolina. ‘Nuff said. Except … we’re gardeners and we must garden! Heat? Humidity? It’s all just more stuff to keep our horticultural minds busy. Does a fungus love heat and humidity? Yes it does. Does your water bill go through the roof trying to keep stuff alive just so it can drown in the next thunderstorm? Probably. Can you keep up with the aphid, spider mite and lacebug outbreaks? Hopefully!

But wait. Remember the 70-degree days we enjoyed in February? Can’t get that in New Hampshire or New York or Nebraska or North Dakota, or a whole host of other states. Then think ahead to October.  Will we worry about snow then? Will our growing season have ended? Nope! Sure it’s hot and humid now, but we can escape to the sea for a breeze or to the mountains for some cooler temps. Yessirree, give me North Carolina every time, thank you very much. Now let’s go out in the yard and be grateful.

Lawn Care
Fertilize warm season grasses (Bermuda, Zoysia and St. Augustine) if you haven’t already. When mowing these lawns remove one-third of the growth. Change directions with each mowing to strengthen root systems and expose different side of the blades to sunlight.

Fertilizing
Continue side-dressing your vegetable garden plants. July is the last time to fertilize landscape plants until next year.

This is an excellent time to take soil samples especially from your lawn. Sample boxes and instructions can be obtained from the extension office.  It is a FREE service until November.

Planting
Veggies that can still be planted include Brussels sprouts, collards, beans, carrots, tomatoes and pumpkins.

A young Brussels sprout plant, ‘Long Island Improved,’ one of three varieties that perform satisfactorily in N.C.  The others are Jade Cross E Hybrid and Royal Marvel. About 85 to 95 days are required from field seeding or transplanting to maturity.

Get ready for the fall garden by starting broccoli, cabbage and cauliflower plants to be transplanted in mid-August.

July is also a good time to transplant overgrown houseplants.

Pruning
– “Bleeder” trees like maple, dogwood, birch and elm can be pruned this month.

– Overgrown hedges can be pruned.

– Coniferous evergreens (they make cones with seeds in them) can be pruned.

– Raspberry and blackberry fruiting canes can be cut to the ground following harvest.

– Rhododendrons, azaleas (I know that’s redundant) and blueberries can have the dieback removed.

– Keep garden mums pinched until mid-month.

– Remove faded blooms on perennials to encourage a second blooming.

Spraying
Insects to be watchful for include bag worms, leaf miners, aphids, spider mites and lace bugs. Oh, yeah.  Japanese beetles, duh. Watch tomatoes for signs of blight and spray as necessary. Continue with rose program. Also continue fungicide program for bunch grapes and fruit trees.

Vegetable pests to watch for:  cucumber beetle (cucumber, ironically enough), flea beetle (tomato, eggplant and beans) and aphids (everything).

Only use pesticides when necessary and ALWAYS follow the label instructions.

There’s not too many extra things to do this month unless you want to build cold frames and greenhouses to be ready for next winter. I recommend you kick back on the deck in the evening with a cool beverage and enjoy summer in this goodly state. 

Further Reading
Browse, or search, Horticultural information leaflets from NC State Extension:  https://content.ces.ncsu.edu/catalog/series/73/

Learn more about Brussel sprouts – https://content.ces.ncsu.edu/brussels-sprouts

Photo credit: Downtowngal, no changes made:  https://commons.wikimedia.org/wiki/File:Young_brussels_sprouts_plant.jpg

Learn With Us, week of June 30

Composting

Sunday, June 30⋅3:00 – 4:00pm Durham County Library – South Regional Library 4505 S Alston Ave, Durham, NC 27713

Description: “Backyard composting” — Discover the basics of successful composting and vermicomposting. Learn how to transform food scraps, leaves, and other organic materials into a nutrient-rich soil conditioner that will benefit your lawn and gardens. Classes are free. Registration at the SRL is required. Register online at the Durham County Library website durhamcountylibrary.org. Click on “Events” to find the full calendar of events. Go to the date of the class and sign up. You can also call the Information Desk at South Regional Library to register: 919-560-7410.

I must Stop the Mock Strawberry (Duchesnea indica)

By Wendy Diaz, EMGV

Last year, I noticed a spreading wildflower around the base of my beautyberry bushes (Callicarpa Americana) in a perennial bed along the south side of my house that I originally thought was Wild Strawberry1 (Fragaria virginiana). It appeared amongst my creeping Jenny (Lysimachia nummularia ‘Aurea’), which I was using as a ground cover. 

Mock Strawberry colony of plants covering ground of ornamental flower bed. Photo by Wendy Diaz on May 6, 2019

This year, it has taken over the bed and migrated into the lawn and even the aggressive creeping Jenny has lost its battle with this plant, which now covers every plant in the bed that isn’t higher than five inches. A lesson that I should have learned a long time ago … if the gardener ignores a few weeds in the garden, the gardener risks bigger issues in the future. The culprit, as it turns out, is a perennial weed commonly called Mock or Indian Strawberry (Duchesnea indica)2,3and not the native wildflower, Wild Strawberry4. The relatively sudden appearance of this plant in my yard is likely the result of birds eating drupes elsewhere and spreading them to my yard2.

Creeping Jenny has been covered by Mock Strawberry in ornamental bed. Photo taken by Wendy Diaz on May 6, 2019

Mock Strawberry (Duchesnea indica)

Mock strawberry is an herbaceous perennial plant of a height between three and eight inches and spreads by runners or hairy stolons3, 5 into large colonies of plants over time. Each plant consists of small trifoliate basal leaves with long petioles that develop from a root crown2. Each leaflet is about one inch across and elliptical with rounded toothed lobes5. Its five-petal yellow flowers of about 0.5-inch diameter appear in spring and develop into tiny edible red tasteless fruit or drupes that are held upright2. Small red seeds form on the bumpy surface of the fruit. It prefers moist soils and partial sunlight and can adapt to regular mowing because of its low growing habit2. It was introduced as an ornamental plant from south Asia.

Five-petal yellow flower of the Mock Strawberry. Photo taken by Wendy Diaz on June 20, 2019
Trifoliate basal leaves and red fruit or drupes of Mock Strawberry. Photo taken by Wendy Diaz on May 6, 2019

Control

To help reduce Mock Strawberry lawn encroachment, it is recommended that one improve surface drainage, aerate when needed and conduct infrequent watering5. If the gardener is interested in chemical control, the recommendation for both pre-emergence and postemergence control formulation is provided in detail on the NC State TurfFiles website5.  In my perennial bed I have decided to control it by hand weeding and mulch. 

Comparison to Wild Strawberry

Wild Strawberry or Scarlet Strawberry can make a desirable ground cover in woodland gardens with some wildlife value1, 4 and it can control erosion on slopes. Mock Strawberry is easily distinguishable from the native Wild Strawberry because its flower is yellow and the Wild Strawberry has a white flower. Other differences include lower growing and smaller leaves of the Mock Strawberry and the drupes are erect. The Wild Strawberry drupes tend to hang downward and the teeth on the leaf edges are sharp-pointed rather than rounded. Best of all, the fruit of the Wild Strawberry is juicy and with a pleasant sweet-tart taste whereas the Mock Strawberry is bland with a dry texture.

Your yard may not have ideal conditions for Wild Strawberry as a ground cover but nevertheless cultural control of Mock Strawberry is more desirable than letting it takeover your ornamental beds and crowding out more desirable lower growing plants.

References

  1. http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=291715&isprofile=0&=

2. https://www.illinoiswildflowers.info/weeds/plants/mock_strawberry.htm
3.  https://plants.ces.ncsu.edu/plants/all/duchesnea-indica/

4. https://www.ncwildflower.org/plant_galleries/details/fragaria-virginiana

5. https://content.ces.ncsu.edu/indian-mock-strawberryor

https://www.turffiles.ncsu.edu/weeds-in-turf/indian-mock-strawberry/

Beetlemania

by Bob Shaw, EMGV

Japanese beetles have emerged in Durham County. We have been picking them from our orchard trees at Briggs Avenue Community Garden since the start of June. This time of year takes me back 40 years to our first house out in Orange County sitting in a large yard, but surrounded by woods. On an early June morning, as the sun warmed the ground, I watched in dismay as clouds of beetles rose from the turf. For the next years, I warred against them — inoculating my lawn with milky spore bacteria (then available only from the county extension agent) and with traps. More about traps later. Each afternoon, I’d come home from work and empty a full gallon of beetles from my traps into a bucket of soapy water. Over the years, I accumulated a large pile (not quite a mountain) of beetle husks. Eventually, I controlled them and my apple trees no longer had all their leaves turned to brown lacework, no longer were my peaches gnawed to brown, nasty pulp.

Japanese beetles on an apple tree.
Photo by Bob Shaw


At Briggs, we don’t have a plague and we manage them with an old plastic container of soapy water. In the cool morning, when they are still lethargic, one holds the container beneath the beetles’ leaf and, obligingly, they drop into it; this works best at 70 degrees or lower. As the temperature rises they are more active and are likely to fly as you approach. Collecting one is very satisfying, even more when a pair is caught in flagrante delicto or, even three or more, when onlookers are present.

We find beetles on, and eating leaves of, roses, apples, peaches and persimmons in the community garden. A few beetles are on our figs, but they haven’t eaten the leaves. Likely the broad, flat, green leaves provide a nice landing zone. But as the population grows, they range more widely: into mint and blackberries.

About traps:  As described above, I used them many years ago and traps saved us. If beetles are a plague, as they were with me, collection in cups of soapy water may not seem practical. However, be aware that beetles must be emptied from the traps every day or two to prevent them from rotting and releasing ammonia which is repellent to other Japanese beetles. Traps also can attract beetles from your neighbor’s yard, increasing the population in your yard. So what? – We want to be good neighbors, don’t we?

Sources & Further Reading

https://content.ces.ncsu.edu/japanese-beetle-1

Coping During Japanese Beetle Season

Date and Place Correction – Learn with Us

Editor’s Note: The Durham Garden Forum lecture for June will take place on June 25, 7 – 8:30 p.m. at the Richard White Lecture Hall on Duke’s East Campus. There is no lecture this Tuesday at Duke Gardens as previously posted here.

Life Favors Conditions That Favor Life – Durham Garden Forum

Tuesday, June 25, 7:00 – 8:30pmRichard White Lecture Hall, East Campus, Duke University. – Note Date and Place Change for the June meeting.

Description: Life Favors Conditions That Favor Life
Jan Little, director of education & public programs Duke Gardens

Current research has documented the tangible benefits provided by nature – including a conclusion that living near natural areas offers benefits to individuals equal to a $20,000 a year raise! Join us to discuss those benefits
and how nature, in our backyard and in our communities, offers a significant impact.

The Richard White Lecture Hall is the second building on the right as you enter Campus Drive from Main Street. There is some street parking available on Campus Drive. A larger parking lot is available in the back of the Epworth building which can be accessed from Buchanan Blvd across from W Trinity Ave.

Lectures free to members, $10 general public
No Preregistration necessary 
durhamgardenforum@gmail.com