Be Proactive to Prevent Vegetable Diseases

When it comes to vegetable diseases, an ounce of prevention is worth a pound of cure. Many diseases can be stopped before they start with smart garden practices.

Spring rains cause spots, dots, and fuzzy blots to pop up in everyone’s vegetable patch. That’s fungi having fun. But whether our weather is wet or dry, fungi, bacteria and viruses stand ready to harm plants. 

So, how do you keep them at bay? Be informed and watchful. Look at your plants often to spot small problems before they get big and use the following tips to prevent disease problems.

If you have repeat offenders – diseases that show up year after year – look for disease-resistant varieties. For example, there are varieties of tomatoes labeled as resistant to both verticillium and fusarium wilt. 

Early blight is a common disease of tomatoes. Photo:  J. Traunfeld, UME

Some plants are available in certified, disease-free starts. Choose potato tubers, garlic bulbs, and asparagus and rhubarb crowns that are certified and disease-free. 

Vegetables hate soggy soil. If your garden area is wet, consider creating a raised bed to improve drainage. Or, grow in containers or move the garden to an area that drains well.

You’ve heard me preach the gospel of compost time and again. But did you know that compost actually discourages some plant diseases? Garden smart by adding compost every year. 

Help prevent disease by spacing your plants properly to encourage good air circulation. Plant labels often give spacing tips as do garden books and websites.

Warm, humid weather invites powdery mildew on squash. 
Photo: UME Home & Garden Information Center

Rain can spread soil-borne diseases, splashing infected soil up on plants’ leaves. So keep your soil covered with an organic mulch such as untreated grass clippings or newspaper covered with straw.

Fungi love wet leaves, so water wisely. Water at the base of the plant using soaker hoses or drip irrigation. And water in the morning, not the evening, so leaves dry before nightfall. 

Practice tough love. Remove infected leaves or pull entire plants if they become badly infected. It’s better to lose one bad plant than the whole row. Don’t compost sick plants: bag and trash them.

Overripe vegetables invite disease organisms. So, harvest your vegetables before they get mushy. 

A thorough cleaning of your vegetable bed at the end of the season is crucial since many diseases can overwinter in the soil. Again, if anything had a serious disease issue, bag and trash it.

If you spot a problem, e-mail your local Extension horticulturist a photo or bring them a sample to identify. Here’s a list of our county offices. We can usually get back to you in a day or two with advice.

For other growing tips and diagnostic help, visit our Home & Garden Information Center website. It has photos, management tools, and a wealth of resources. There’s even an Ask Extension link to submit gardening questions to certified horticulturists.

Enjoy your vegetable garden this year. A few seeds and transplants, some rain, sun, and a watchful eye will have you enjoying fresh, healthy homegrown food all season long.

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension. This article was previously published by Herald-Mail Media. Read more by Annette.

This article was previously published by Herald-Mail Media.

Grow It Eat It Celebrates 15 Years of Teaching and Promoting Food Gardening!

Food gardeners are an important part of any local food system. In Achieving Sustainability through Local Food Systems in the United States (PDF) (2013), agricultural economists Dale Johnson and James Hanson, Ph.D. state: “By far the greatest, but often overlooked, local food source in the United States is gardening.”

About 35% of Maryland households are doing some type of food gardening and have lots of important questions: What’s this worm eating my kale? How do I improve my soil and test it for lead? How do I start a school garden? Where can I take a vegetable gardening class?

Since 2009 many residents and communities have received science-based food gardening answers and help from Grow It Eat It (GIEI)– one of the six major sub-programs of the University of Maryland Extension (UME) Master Gardener Program that teaches and promotes home, school, and community food gardening. This article serves to introduce this amazing program and some of its successes. I plan to write a second article later this year on some of the exciting 2023 GIEI projects from around the state.

What is GIEI?

Grow It Eat It was developed late in 2008 by UME staff, faculty, and volunteers in response to the Great Recession. Many people were already interested in trying their hand at food gardening as a way to eat more fresh produce and connect with nature. The economic collapse forced folks to find ways to reduce household expenses.

The main GIEI objective has been to increase local food production by combining the power of grassroots education and technical assistance delivered by field faculty and Master Gardeners, with UME’s digital gardening resources. Master Gardeners (MGs) have taught hundreds of classes, developed demonstration gardens, and helped thousands of individuals and groups start food gardens and learn and use best practices. Residents can learn about GIEI classes and events by visiting their local Extension web pages and connecting on social media. MGs also help residents solve food gardening problems at Ask a MG Plant Clinics around the state. The Home and Garden Information Center (HGIC) supports GIEI by training MGs, creating and maintaining digital resources, and answering food gardening questions through the Ask Extension service.

GIEI intersects and collaborates with other MG sub-programs– Bay-Wise Landscaping, Ask a MG Plant Clinic, Composting, and Pollinators– and with UME’s nutrition, natural resources, youth development, and urban ag programs. This helps the program address four of the five Strategic Initiatives guiding the College of Ag & Natural Resources.

5 strategic initiatives of the University of Maryland Extension College of Agriculture and Natural Resources

As the faculty lead, I have loved every minute spent working with UME faculty, staff, and volunteers to shape, improve and expand the program. Master Gardener Coordinators and Volunteers decide how to best shape GIEI to meet local needs. The State MG Office organizes regular GIEI statewide planning/sharing meetings and continuing education classes, and provides seeds, teaching, and marketing materials. MGs responded to the pandemic by moving GIEI classes online. GIEI projects and activities steadily increased in 2021 and 2022 and should surpass pre-COVID levels in 2023.

packets of sunflower and green bean seeds
75K seed packets have been distributed to residents to promote food gardening and the UME MG Program. Sunflower and bean seeds in 2023!

Program Outcomes and Impacts (2009-2022)

  • 121,894 MG volunteer hours valued at $3.05M
  • 1,832 classes and workshops for 47,000+ residents
  • 70 tons of produce grown in MG demonstration gardens donated to local food banks and pantries
  • 87 MG advanced training classes on Vegetable Plant & Pest Diagnostics, Hydroponics, Community Gardening, Youth Gardening, Organic Gardening, and other topics
  • Hundreds of web pages, videos, and blog articles
  • Awarded “UME Signature Program” status in 2017
  • Technical assistance and support for dozens of community and school gardens
  • “Year of…” initiative featuring a different crop or vegetable family each year. 2023 is the Year of Sweet Potatoes!
  • Inspired Shauna Henley, Ph.D. to create Grow It, Eat It, Preserve It
  • Inspired the Bay-Wise Landscaping Program to create a Food Gardening Yard Stick (PDF)
  • Evaluation data:
    • 2009-2011 statewide survey of GIEI classes taught by MGs (n=2,532). When asked “Why do you want to start a vegetable garden?” 77% selected “to contribute to a more healthy diet” and 65% selected “to save money on food costs”
    • 2009-2011 6-month follow-up statewide survey of GIEI classes taught by MGs (n=349). As a result of taking the class, 36% started a vegetable garden, 37% became more confident gardeners, and 31% increased garden productivity
    • 2009-2010 statewide follow-up survey of the GIEI website (n=858). “Made my garden more productive” (44%); “Made me a more confident gardener” (40%); “Started a vegetable garden” (31%)

GIEI Delivers Public Value

GIEI projects add public value to communities. For example, MGs in Frederick County worked closely with homeless families and public housing residents to build raised beds and teach gardening skills, and MGs in several counties partner with SNAP-Ed educators to teach food gardening to students attending Title I schools that provide free and reduced meals.

Here are just a few of the many notable GIEI projects:

a woman and a girl planting a container garden
In addition to donating produce to the Manna Food Center, UME MGs in Montgomery County started the Cuidando Jardineros Program (“Growing Gardeners”). They gave 244 families (majority English as a second language) a 5-gallon bucket garden in 2015. A 6-month follow-up survey showed success in growing and using fresh produce.
boys harvesting carrots from a container garden
Youth in the Summer Youth Enrichment Program (SYEP) learn about growing and using herbs in the UME, Prince George’s Co. MG Demonstration Garden in Clinton, MD.
A luffa “highline” was featured in the MG Learning Garden at the Maryland State Fair last summer.
Master Gardeners ready to engage visitors to the Learning Garden at State Fair!
two people working on a trellis in a garden
Sandee Heredia and Derex Thompson, both UME, Charles Co. MGs, refreshing a bed in the  “Seeds of Hope” Community Learning Garden at the Southern MD Food Bank in Waldorf, MD. MGs help manage the garden and used it as a teaching/demonstration site.
a person holding a container of produce from a garden
Tori Chrichlow, UME, Charles Co. MG with produce from the food bank garden that feeds people in need.

What’s next for GIEI?

  • Move toward greater Diversity, Equity, Inclusion, and Respect (DEIR) by working with community partners and other UME programs to learn and meet the food gardening needs of under-served residents
  • Teach and demonstrate climate-resilient practices like Improving/protecting soil, growing heat-tolerant crops and cultivars, season extension, cutting greenhouse gas emissions and food waste, and supporting/promoting local agriculture
sign reading how to harvest banana peppers
Signage in Harwood Community Garden, Baltimore City

Enjoy your harvest this year!

By Jon Traunfeld, Extension Specialist, University of Maryland Extension, Home & Garden Information Center. Read more posts by Jon.

How to grow a healthy garden

It’s easy to get overwhelmed by the sheer volume of gardening advice in books and websites. So I thought I’d simplify things by sharing my top 10 tips for keeping a garden healthy. 

Start with your soil. Healthy soil grows healthy plants. So get a soil test to know what you have and need.  

Add compost or other organic matter regularly to enliven the soil and keep the soil community happy. This intricate web of beneficial microbes, fungi, bacteria, worms, and more is crucial to healthy plants. 

Well-adapted native plants such as this white penstemon naturally resist pests and disease. Photo: Kathy Vesely

Minimize soil disturbance. Every time you turn the soil, you bring up weed seeds and wreak havoc on the soil community. So dig and till minimally.

Keep the soil covered with plants, an organic mulch, or cover crops. Bare soil invites weeds, encourages soil-borne disease, and promotes erosion. 

Put the right plant in the right place. Choose plants that suit the site whether it’s sunny or shady, wet or dry. This matchmaking helps plants not only survive but thrive.

Use native plants. These tough, well-adapted plants need less water and fertilizer. Since they co-evolved with native wildlife, they support pollinators and other native species best. 

Encourage beneficial insects. These are the good bugs that help control bad bugs. Nine out of ten insects are beneficial, naturally controlling the few true pests. Put them to work for you. 

How? Reduce or eliminate chemical pesticides which kill both good and bad bugs. Use organic products instead and try other controls like hand-picking or floating row covers.

Further, encourage beneficial insects by planting a wide variety of plants to provide food and shelter. Add a rock to a birdbath so insects can sip. 

Wait to cut back perennials and grasses until spring to give beneficial insects a safe place to overwinter. Many tuck into hollow stems or leaf litter.

Check your plants often. When you’re strolling, be patrolling. Look for spots, yellowing, or other changes that might be clues to a problem. Early detection makes fixes easier.

If you live in Washington County, Maryland, e-mail or call me if you need help identifying an insect or disease. Just send me a photo or bring me a sample. If you live in another area of Maryland, contact your county or city Extension office, or send your questions to Ask Extension.

Many problems are preventable. Honest. About 80% have cultural or environmental causes and aren’t due to pests or diseases. So there’s much we can do to prevent problems.

Water wisely. Water in the morning and avoid overhead watering. Leaves that are wet overnight tend to have fungal problems.

Removed diseased plants. Add compost which naturally suppresses some diseases. Space plants so air circulates. Cover bare soil so rain doesn’t splash fungal spores up onto plants.

At the end of the growing season, thoroughly clean up vegetable plant debris which can harbor harmful overwintering insects and disease.

There you have it, my top 10 tips for a healthy garden. When you work with nature, not against it, you naturally limit pests and diseases, grow more resilient plants, and build a healthier garden and community.

That’s a very good feeling indeed.

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension. This article was previously published by Herald-Mail Media. Read more by Annette.

This article was previously published by Herald-Mail Media.