How to Grow Heirloom Tomatoes for Vibrant Taste and Varied Color

Learn how to grow heirloom tomatoes, a few of our favorite varieties, and tips for planting them in the garden to prevent common problems, pests, and diseases.

There’s a striking difference in taste between a homegrown vine-ripened tomato and a store-bought tomato picked early and trucked across the country.  Some of that difference has to do with freshness and ripeness. But some of it has to do with tomato varieties.

“Heirloom” is a broad term for older tomato varieties.  These may be quite different in size (from tiny cherries to hefty slicers), shape (globe, grape, pumpkin…), and color (red, pink, purple, orange, yellow, green, black…) 

But most were bred more for flavor than for long shelf life or uniformity.  And all are open-pollinated not hybrid, so you can save seeds that will grow into plants similar to their parents.

Growing Heirloom Tomato Plants in the Garden

Fertilizing

Tomatoes are heavy feeders which especially benefit from having abundant phosphorus in the soil. Rodale’s Garden Problem Solver recommends supplemental feeding every 2-4 weeks.  But excess nitrogen can be a problem, encouraging the plant to put out too many leaves rather than focusing on fruit.

When I transplant seedlings out into my garden I add bone meal as well as compost to the planting holes. I spray my tomatoes with fish emulsion fortnightly, and with seaweed extract twice or thrice during the growing season.

Spacing

Spacing recommendations for tomatoes vary widely.  This depends partly on the type of tomatoes you are growing.  

Determinate tomatoes have a bushy growth pattern. When the bush reaches a certain height—perhaps 4-5 feet—it stops growing. 

Indeterminate tomatoes have a vining growth habit and keep growing until they die.  Many heirloom varieties are indeterminate and robust. 

Spacing also depends on the system you will use to support them. Rodale’s Garden Problem Solver says plants can be set 12-18 inches apart if they are pruned and trellised.  The Georgia Extension suggests setting plants at least two feet apart in rows four to six feet apart and staking or trellising them.   

I’ve found that I have less trouble with fungal disease if I space my plants widely.  I plant two staggered rows of tomatoes in a 4-foot-wide bed, setting plants 3 feet apart in the row.

Popular Heirloom Tomato Varieties

There are many varied and striking heirloom varieties.  Here are three favorites I’ve grown:

Cherokee Purple

Cherokee Purple is named after the striking color of the fruit. It produces fruits with purple-brown skin.

Their shoulders tend to stay green even when ripe, and their flesh is deep red.  I think of their taste as smoky; Fedco Seeds offers grower descriptions including “sweet juicy winey” and “rich Brandywine flavor.”

Pink Brandywine

Pink Brandywine is one of the best-known heirloom varieties.  It has very large fruits, up to 1 pound, shaped almost like pumpkins.  The flavor is rich and satisfying.

I used to love Brandywines but finally gave up on growing them because they repeatedly succumbed to diseases.  But I’ve heard other growers describe Brandywine as disease-resistant.  This may depend on the particular strain of seed.

Golden Jubilee

Golden Jubilee is a personal favorite that’s not quite as well known. Its fruits, which average about 8 ounces, are smooth, sweet, and deep yellow-gold. They are somewhat low acid, so I take care not to have too high a percentage of them in the batches I can, but they’re lovely for fresh eating.

Some other distinctive heirloom tomatoes include German Johnson and Homestead.

When and How to Plant Your Heirloom Tomatoes

planting tomatoes in garden

Tomatoes are highly frost-sensitive, but they need a long season to mature. Buy established seedlings once the danger of frost is past, or else start your own seeds indoors.

Here in northern New York State, I start three successions of tomatoes from twelve to eight weeks before our last frost date (May 31). 

In warmer climates, you can start much earlier. The Georgia Cooperative Extension recommends starting tomatoes four to seven weeks ahead of their frost-free dates, sometime between late March and early May.

Keep your seedlings in a warm, sunny place. Give them light foliar feedings every week after they develop their first true leaves and before you transplant them outside.

Transplant your tomatoes out when all danger of frost is past. Check with your local Cooperative Extension about the frost-free dates for your area. 

I set one fifty-foot bed’s worth of tomatoes out in mid-May if the weather looks mild and my early succession plants are getting leggy.  I have enough frames and blankets to cover that many plants if a frost threatens.

When it’s time to plant out, follow these steps.

  1. Dig deep planting holes and fill them with compost and whatever other soil amendments you find useful. 
  2. Strip off the bottom leaves from the plants, leaving at least 2 or 3 healthy pairs of leaves at the tip.
  3. Bury the plants almost up to the bottom pair of remaining leaves; roots will grow from the stem area and help your plant grow stronger. 

I set my seedlings in diagonally so I can bury plenty of stem without requiring really deep holes.  Water your seedlings well.

young tomato plants growing in garden

Maintaining Your Tomato Plants

Watering

Tomatoes do best with plenty of water. 

Rodale’s Garden Problem Solver recommends giving them between 1  and 1 ½ inches of water a week.  But frequently wetting the leaves will make them more vulnerable to fungal diseases. 

I use a drip irrigation system with spaced emitters that water the roots without wetting the leaves. Before I started that system, I set my plants in depressions or “saucers” in the bed and flooded those saucers with water. I took the spray nozzle off the hose and set it at ground level to fill the saucers.

Pruning

Some gardeners prune their tomatoes. Some pinch out “suckers” (small branches which grow at the junctions between the established branches and the stem). 

Others prune more rigorously so that their plants develop one single tall stem (or, perhaps, two) to train up a trellis. 

I don’t prune mine.  The high winds in our area make high trellises impractical.  And since I usually lose some leaves to fungal disease, I prefer to start with extra leaves. 

But some growers say that pruning leaves the plant more open and less prone to disease. I do remove dead or diseased leaves at least once a week.

Common Problems With Tomatoes

Disease and Environmental Stress

Tomatoes are quite susceptible to a wide range of fungal diseases, including anthracnose, septoria spot, fusarium wilt, early blight, late blight, and many more. 

Heirloom varieties often have not been bred for disease resistance and may be more susceptible.  There are several ways to improve their chances.

One method is to graft heirloom cuttings onto hybrid rootstocks.  This takes a certain amount of time and skill, and also requires starting many more plants than you plan to end up with; I haven’t tried this myself.  The Colorado Extension offers an excellent guide to grafting tomatoes if you’d like to try it.

Another method is to keep the foliage dry by supporting plants, spacing them widely, watering at the roots not from the top, and mulching.  I’ve done all these things to keep my heirloom tomatoes healthy.

I’ve treated diseases with organic fungicides, including store-bought Bacillus subtilis and a homemade mix of 1 part milk to 9 parts water.  

Sometimes I’ve used these sprays preventively.  I avoid composting tomato fruits or plants, so as not to recycle diseases from one year to the next.  Instead, I dump the plants in the woods across the road. 

  • Environmental stresses can also lead to what looks like disease symptoms.
  • Excessive or irregular watering can cause the blossom ends of fruits to rot.
  • Sun, wind and drought can cause yellowing and rolling of leaves.

Cornell University’s “Vegetable MD” tomato page offers helpful visual guides to tomato symptoms, possible causes, and cures.

Insect Pests

  • Tomato hornworms are large pale-green caterpillars that can strip a plant bare in a hurry.  They can be handpicked or sprayed with the organic pesticide Bacillus thuringiensis (Bt.) 
  • Aphids or mites may suck the juices from leaves. Encourage ladybugs or spray with organic insecticidal soap to control these. 
  • Cutworms may also cut off newly transplanted tomatoes. You can protect seedlings from cutworms by putting stiff paper collars around the plants. Push these one inch down into the soil).

Alternatively, you can sprinkle cornmeal in a circle around the stems. The cutworms eat this, it expands in their stomachs, and they burst.

Summary or Wrap up

Heirloom tomatoes require a little extra TLC, but their vivid color and flavor are well worth it.  Experiment with different varieties and see what you like best.

Like it? Pin it!

How to grow heirloom tomatoes - Pinterest Pin