Few things can compete with a juicy, flavorful tomato recipe on a hot summer day — especially when you’ve grown the fruit yourself. It isn’t difficult to grow delicious, healthy tomatoes at home, but there are some mistakes that can have serious consequences, like stunted growth, less fruit production and diseases. But with a little care and attention, even beginners can grow a successful tomato harvest.
We spoke with two gardening experts, who urge you to avoid these common tomato growing mistakes — from planting at the wrong time to forgetting to prune. Here’s what they had to say:
Planting too early
The best time of year to plant tomatoes will depend on your weather and climate. Before you grow tomatoes outside, nighttime temperatures should be consistently above 50 degrees, with daytime temperatures 60 degrees or higher. Seedlings are very sensitive to frost and low temperatures, so planting them too early in the season might cause them to die or stunt their growth.
Failing to provide nutrients
Don’t forget to feed your tomatoes. “Especially once they start producing fruit, your tomatoes need a consistent supply of nutrients to keep them producing and happy,” says Brian Brigantti, founder of Redleaf Ranch and author of Gardening for Abundance. “When I first plant my tomatoes, I throw in a scoop of organic tomato fertilizer at the base of the hole before putting the plant in. Once my tomato starts to grow and produce fruit, I mix in fertilizer around the base of the plant every 3 to 4 weeks.”
Forgetting to prune
Pruning is essential to the overall health of tomato plants. Failing to prune suckers (shoots that appear at the base of the main stem and side branches) and lower leaves can create excessive foliage and limit fruit production. “With side shoots left on, you get too much air congestion and with that potential pests and diseases,” says Sarah Raven, English gardener and author. “People are scared to do it in case they pinch out the wrong bit, but you MUST.”
“Tomatoes are tough plants; they can handle a good snipping,” agrees Brigantti. “I’d also suggest pruning any leaves that make direct contact with the soil as those can fester soil-borne diseases. Don’t be afraid to prune any excess arms that your tomato plants produce. Every arm that grows takes energy from the plant, so if you want to redirect energy to more fruit production on the arms that are already producing, snip off any new arms.”
Inconsistently watering
Tomato plants thrive in moist (not soggy) soil. Experts suggest giving tomato plants 1 to 1.5 inches of water each week, slightly more often during the height of summer.
Don’t trust yourself to consistently water your garden? Raven suggests, “Get an irrigation system on a timer so that you give the same watering for a month at a time, without having to think about it.” Remember to consider rainfall and adjust your schedule if there’s been excessive rain, since overwatering can lead to root rot.
Planting seedlings too close together
Tomato seedlings should be planted 18 to 24 inches apart. Without proper spacing, tomato seedlings won’t have enough circulation, which can increase the risk of pests, plus they’ll be competing for sunlight, water and nutrients if they’re planted too close together.
Not providing proper support
Whether you have a determinate or indeterminate variety, your tomato plant needs support — tomato cages, plant stakes or a more permanent structure, like a trellis, will do the job.
“Tomatoes have a habit of sending out an abundance of arms that’ll hold the fruit it produces,” says Brigantti. “Without proper support, the weight of the arm can become too much to bear and cause the arms to sag or even snap off.” The plant will continue to send out arms throughout the season, so you’ll need a tall, sturdy tall support system.
Pro tip: “My personal favorite ways of trellising unruly tomatoes are with cattle panels that you can mold to form an arch,” says Brigantti.
Harvesting at the wrong time
A failure to harvest tomatoes when they’re ripe can cause them to split or spoil, which attracts unwanted insects and pests to your garden. You can harvest tomatoes when they’re fully ripe or a few days prior to allow them to ripen indoors.
Choosing the wrong variety
From heirlooms tomatoes to tiny cherries, tomatoes come in many shapes and sizes. Consider the size of your space, and whether you want a determinate or indeterminate variety. Determinate tomatoes take up less space and grow like a bush, making them ideal for container gardening, but they typically only fruit over a two-week period. Indeterminate tomatoes grow longer vines up to 8 to 10-feet tall and tend to produce flavorful fruit all season long.
Raven says, “I always advise to go for an interesting, taste-packed variety” — likely an indeterminate like a big beef or cherry tomato. “I prefer to grow from seed instead of a seedling for the best result,” she adds. “Many available seedlings in stores can be not that much more interesting in taste than a supermarket tomato.”
Alyssa Gautieri (she/her) is the associate lifestyle editor for Good Housekeeping, where she covers all things home and interior design. Prior to joining GH in 2022, she wrote for publications including ELLE Decor, Chairish, BobVila.com, Unique Homes Magazine and LODGING Magazine, in addition to crafting product copy for home brands like BrylaneHome and VIGO Industries.
