As many gardeners know, growing tomatoes in the Mid-Atlantic can be difficult. Diseases and pests can afflict any vegetable, but it seems to be most frustrating when that happens to tomatoes. However, there’s hope. Choosing the right tomatoes for our region and maintaining proper growing conditions will help tremendously.

I spoke with heirloom tomato expert Tim Mountz, owner of Happy Cat Farm in Kennett Square, Pennsylvania, about growing great tomatoes in our region. He says there are four key things to keep in mind: pH, light, temperature, and humidity.

1. Check the pH of your soil

Local extension services will usually provide soil testing and recommend amendments according to what is being grown. A simple soil pH test can also be found at local garden centers or online stores.

2. Provide the plants with the correct amount of light

Tomatoes need full sun. Tim says this is crucial and that four to six hours of full sun is just not enough. Think of a field with sun from dawn to dusk—that is the optimal amount of sun needed for healthy tomato plants.

3. Grow your seedlings and transplants at the right temperature

When starting your seeds, maintain a soil temperature of 70°F or greater for germination. Wait until the air temperature will not fall below 50°F to plant seedlings outside. Lower temperatures will result in slow germination and growth. Tim says, “They will catch up in the end, but it’s not the end we want.” At the farm, Tim aims to plant tomato crops in the third week of May. He says Mother’s Day weekend is also a good time to plant.

4. Watch out for humidity

Mid-Atlantic summers bring high humidity, which can be detrimental to tomato crops, breeding disease and fungus. Tim advises providing adequate air circulation by staking the plants to keep them off the ground. If the tomatoes do develop a fungus, he recommends a biological fungicide called Serenade. Organically approved, it contains beneficial bacteria that suppress the fungus. It won’t harm insects, and the fruit can be eaten at any time after application.

Best Tomato Varieties for the Mid-Atlantic

After providing the ideal growing conditions, Tim identified a few varieties that he believes are the best tomatoes to grow in the Mid-Atlantic.

‘Brandywine’ tomato

A tried-and-true variety, this tomato has been grown in Pennsylvania’s Brandywine Valley for a long time and is still a Happy Cat Farm favorite. You cannot go wrong with this big, red slicing tomato. The enormous (sometimes up to 1 pound), juicy fruits are great for sandwiches and salads. Just make sure to stake the plants to keep the heavy fruits off the ground.

‘London Grove’ tomato

Smaller than ‘Brandywine’ but still a local favorite (a Quaker heirloom from Chester County, Pennsylvania), ‘London Grove’ tomatoes are perfect for cooking and making sauces. This meaty variety has tons of flavor with what Tim calls “just a touch of juice,” and the plant yields lots of fruit.

‘Black Krim’ tomato

This is Tim’s all-time favorite tomato. He believes the balance and flavor of ‘Black Krim’ are unbeatable. It is a medium to large slicing tomato with beautiful dark burgundy tones that get darker with more sun. He describes the flavor as “smoky, salty, and complex.”

‘Matt’s Wild Cherry’ tomato

For those looking for a smaller tomato, Tim’s pick is ‘Matt’s Wild Cherry’. These perfectly round, petite tomatoes are packed with flavor. This variety also has some resistance to early and late blights. They may not yield as much as a hybrid, but the flavor is worth it.

‘Green Grape’ tomato

For those who do not have much space, Tim suggests ‘Green Grape’, which is also great for container gardens. This zesty, tart tomato is green when ripe, with some yellow tones. It’s perfect for patio gardens—just make sure it has enough sun.

Whether you are growing a giant slicing tomato like ‘Brandywine’ or a sweet cherry-like ‘Matt’s Wild Cherry’, just follow Tim’s basic growing rules and you will have a successful tomato yield here in the Mid-Atlantic. For more tips on growing tomatoes, read all about tomatoes here.

—Michele Christiano has worked in public gardens for most of her career. She currently works as an estate gardener maintaining a private Piet Oudolf garden.