Real experts who have grown real gardens in the real world on the Front Range tell you  what you need to know to have you rooting for your very own crop of successes this summer season


Did Evelyn Mention They’re the Divas of the Garden?

By Dave Perry, staff writer

A store-bought tomato is like kissing a mirror. Yes, home-grown tomato fans love the vine-ripened fruits of their labors that much. And the red balls developed to look like pretty tomatoes and stay like that in the produce department weeks after they were picked? They’re only slightly better than eating a picture of the real thing.

Once you’ve had an exotic Black Krim that hanged on the vine in the hot sun until you couldn’t stand it anymore, you’ll be anxious to have more.

Anybody can grow them, says master gardener Evelyn Alton. She’s one of Colorado State University gardening experts lending advice to Front Range residents who’ve never touched dirt with their own hands, as well as those veteran gardeners honing their skills.

All you need to succeed is a little determination and a little knowledge, she said.

The rules

These are the edicts that Alton and every seasoned tomato gardener say you must pay attention to: sun, heat, cold, soil and water. Everything else may be important, but paying attention to these few mandates are what it’s all about.

“Tomatoes are the divas of the garden,” Alton said. “They have to have it their way.”

Tomatoes are really very easy to grow, as long as you play by their rules.

What do you want?

Do you want sweet, juicy cherry or grape tomatoes to pop in your mouth as snacks or toss in a salad? Do you want a big crop of luscious reds to make into sauce and save? Do you want to slice up a ruby red treat for bagels and cream cheese or a caprese salad that will make you shiver?

Since that’s settled, here’s what you need to know: determinate and indeterminate. The first is a tomato plant that blooms all at once, and then sets tomatoes all at once, which pretty much have to be picked all at once. These plants are great for canning and preserving tomatoes and sauces. But if you want a plant that offers tomatoes all summer long, it’s not going to happen. Instead, if you don’t eat or can them, they go to the office after your neighbors quit answering the door. Unlike those flavorless things in the grocery store, real tomatoes have a pretty short shelf life.

Indeterminate tomatoes bloom a little, set a little, and keep doing that until the plant dies. If you treat them right, the first frost will kill them before you can.

Where will they live?

Big open garden? A little patch in the yard or just space on the balcony or patio for some pots?

If this year’s crop will only come from containers, it’s not a problem. But choose smaller plants and the largest containers you can manage, no less than about 3 gallons, experts say. Tomatoes love room, water and sun. Good choices for pots are cherry-like tomatoes and smaller, earlier varieties. The plants are smaller and easier to maintain. For expert advice on container gardening, see page 45

No matter where you’re going to raise tomatoes, this is the world your tomatoes live in, and it’s a small world.

Go get ‘em

Research a little online about tomato variety characteristics. This is personal preference. Striped tomatoes are popular now, nice and acidy but still sumptuous. Black Krims are a favorite, dark and ugly but with fruit so strikingly good you won’t want to share your crop. Bloody Butchers bear fast and offer a smaller, plant and fruit. Pick a plant that’s about 7 inches tall or better. Health is more important than size here. If there are noticeably yellow or wilted leaves, choose another. Look closely for pests. Don’t bring home trouble. The most important feature will be the stalk. It must be strong and healthy. Avoid damaging the stalk when your handling and planting tomatoes, Alton says. Even a slight pinch can damaged tissue in young stalks. She recommends pretending you don’t have an opposable thumb if you have to handle it at all.

It’s all about the sun

No matter where that patch of dirt or pot of soil is, it has to get at least 6 hours of direct sun a day. Tomatoes love the sun. They hate the cold. They hate to be soggy and cold worst of all. And they If you’re going to plant tomatoes on a patio or near a fence, don’t guess. Look to make sure it gets enough sun. Realize, however, that Front Range summers can be brutally hot. So if you have a place in your yard or garden that soaks up full sun all day and then offers a little shade in the afternoon, that’s perfect. If your babies will be getting a UV bath from dawn to dusk, you just need to make sure they get enough water, Alton says.

When do they move in?

Be patient, Alton says. The biggest mistake most mile-high tomato fans make is setting out tomatoes too soon. Cold, and especially cold soil, stunt tomato growth. Watch the weather for a prediction of three consecutive days of overnight lows staying above 55 degrees. Think mid-May at the earliest and probably Memorial Day. They’ll grow if you plant them earlier, but cold roots and even colder greens make for a lesser or even no crop. And there’s heat to consider, too. You have to plant before daytime temperatures by 10 a.m. get above 80 degrees. So probably no later than Father’s Day. And if you plant that late, pick a variety that produces faster rather than slower.

When you buy your plants, don’t plant them that same day. They’ll die or stunt and you’ll be looking for mirror

kisses in the grocery store in August. The plants must be “hardened” for 3-5 days, Alton says. All that means is that you let them have increasing exposure to the great outdoors over a few days. Set them out in a fairly shady spot for a day. Bring them in at night. Then let them have a few hours of direct sun. Then shade. Then bring them in at night, unless the lows are only about 60 degrees. Make sure they stay watered in their pots. Then more sun, less shade and a night on their own. Plants scalded by sun or stunted by cold don’t produce fruit.

Living arrangements

Bigger roots mean bigger crops. Tomatoes not only need room to grow, they need room for more roots. That’s why bigger pots are best. But even in the garden they need a home where roots can easily spread and get the two things they must have: water and oxygen. The soil has to be loose and damp all the time. Not wet. Not soggy. Damp. Invest in good potting soil, or add lots of amendments if you’re planting in the area’s infamous clay soils. If you’re not comfortable creating a good mix from perlite, compost, mulch and other additives, use a prepared mix. Clay soils pack around roots, don’t drain water and smother the roots. The less compact, the better.

Moving day

The idea here is to create an opportunity for your tomato to grow as many roots as possible. That’s why loose soil conditions are so important. So, too, is how you move your Brandywine or Abraham Lincoln into its permanent home. After making sure your plant has been hardened and is ready to rough it, pull about one-third of the plant’s bottom leaves off. Yes, really. You’re going to bury the roots and the newly exposed stem in the loose soil. that buried stem will sprout new roots, making your plant healthier, hardier and more prolific, Alton says. Dig a hole big enough to accommodate the roots and plucked stem, and about twice that size around. Drop in the tomato plant and fill the hole with loose soil. Alton recommends “trenching” your plants instead of typically planting them vertically. “The additional root growth is substantial,” she said. More roots. Tougher plants. More tomatoes. Dig a trench instead of a hole about half the length of the roots and stem to be buried. For a 7-inch plant in a 4-inch pot, you’re looking at about 6 inches. Remove about one-third the lower leaves and then lay the tomato in slanted-sideways, a little at an angle, in the trench. Cover the roots and bottom stem, but gently bend the rest of the stem and leaves some so that it protrudes from the level surface after you bury it. Alton demonstrates how to do this on a video at Don’t worry about the top of the tomato plant jutting out of the dirt at a weird angle. Within a few days, it will begin to right itself. Alton says this method keeps the plants roots closer to the surface, and warmer. Cold roots mean slower-growing plants and fewer tomatoes. Don’t pinch or manhandle the stem. If you don’t trust yourself, plant it normally. “But I really recommend this for healthier plants.”

How much water?

This is the most important question and the hardest to answer. “Think damp,” Alton says. Not wet, not moist, never soggy and never dry. “Damp.” Hotter, windier days mean more water. Cooler and rainier days mean less. It’s not good to stand over your plant once a day  with the hose running full blast and drown your tomatoes in 30 seconds. Drip systems are perfect, but fairly slow water once a day, making sure that when you come back the next day and you stick your finger in the dirt the soil is just “damp.”

“Colorado is a windy desert,” Alton says. Keep a close eye on the water.

Should I fertilize?

Yes. Choose a fertilizer intended for vegetables and preferably tomatoes. It will be higher in phosphorus and lower in nitrogen than house plant or grass products. Read the directions, Alton says, and follow them. Don’t be tempted to overdo it. You might get big, beautiful plants — that never produce fruit. Or, you can outright kill them with too much fertilizer. Less is best, and weaker is better.


1. You’re going to need a stake or cage. Tomato plants can’t support the weight of their own fruit. Install this when you plant the tomato so you don’t damage or interrupt the roots or stalks later on. Use garden tape or ties to gently attach the stalk to a stake as it grows.

2. Pinch some of the blooms off, especially heavy bloomers. Don’t get greedy. Fewer, better tomatoes are what you’re shooting for. “I don’t like to do it either,” Alton said, but it has to be done. Make sure not to pinch them all off. For slicing tomatoes, maybe pinch off 25 percent of the blooms evenly across the plant. For sauce and cherry tomatoes, maybe 10 percent.

3. Weed. Water. Watch. Keep weeds away from your tomatoes. Keep the water consistent so the soil is always damp. Watch for over-watering and pests. Yellow leaves, curled leaves and bugs mean trouble. Many different problems have similar symptoms. Call a CSU master gardener at 303-730-1920 for help, or see a garden professional. If the problem is aphids or mites, there are numerous safe solutions available in garden centers.

4. If we get a freak cold spell, cover the plants overnight. Protect them from hail with netted hail guards.


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