Indigo Apple Tomato

The blue tomato trend traces back to one lab, not one tomato

Walk any seed catalog today and you will find a wall of tomatoes with indigo, blue, or midnight in the name. The Indigo Apple tomato is one of the best of them, but it is not where the story starts.

That whole color actually traces back to a single breeding program at Oregon State University. It was led by a vegetable breeder named Jim Myers, whose work in the 2000s produced the first tomato carrying the same blue purple pigment found in blueberries.

Indigo Apple is not one of his official releases. It is a variety bred by an independent breeder using that same genetic breakthrough, crossed and stabilized into something new.

This guide covers where that color actually comes from and how to read ripeness on a fruit that looks purple long before it is ready. It also covers how to grow this variety well.

What the Indigo Apple tomato actually is

This is a medium sized tomato, usually 4 to 6 ounces, that ripens with deep blue purple shoulders fading into a red base. The color shift depends heavily on sun exposure, since the pigment only develops where light actually hits the fruit.

Cut one open and the flesh runs a rich, dark red with a purple tint. The juice itself can stain your hands a faint purple. It is a genuinely striking fruit to slice at the table.

The plant is a tall, vigorous indeterminate vine with regular leaf foliage. Growers describe it as manageable rather than overwhelming for its size. Expect ripe fruit around 70 days from transplant, on the earlier side for a tomato this unusual.

The flavor is rich and sweet with real juiciness. That is a genuine surprise for anyone expecting a novelty tomato bred mainly for color.

Where the blue actually came from

The full backstory is worth knowing, since it explains why so many tomatoes now carry this color. The pigment behind it is anthocyanin, the same compound that colors blueberries, purple grapes, and red cabbage.

Ordinary tomatoes do not make it. Wild tomato relatives collected decades ago in Chile and the Galapagos Islands carried the trait. It took years of patient crossing to move that trait into a tomato anyone would actually want to eat.

Jim Myers picked up that thread in the early 2000s at Oregon State University. A graduate student had spotted the unusual pigment in old wild tomato stock. Roughly a decade of breeding work later, he released the first blue tomato in 2011.

From there, the trait spread. Independent breeders and hobbyists crossed that original blue genetics into countless new varieties. They chased better flavor, different shapes, and new color patterns on top of the same underlying pigment.

Indigo Apple is a second generation cross, not an OSU release

This is the detail that clears up a lot of confusion at the seed rack. Not every tomato with indigo in the name came out of the Oregon State program itself.

Indigo Apple was originally crossed by PKS Heirlooms, then selected and stabilized by breeder Brad Gates of Wild Boar Farms in California. One of its parent lines traces back to OSU Blue. That connects it directly to that original breeding work, without being one of Myers’ own named releases.

That makes it part of a second wave of blue and purple tomatoes. Independent seed companies and hobbyists bred these once the original genetics became available to work with. Many of today’s most popular blue tomatoes share that same origin story.

How to tell when a purple tomato is actually ripe

Here is the practical problem this color creates. On a normal red tomato, color tells you almost everything about ripeness. On this one, the fruit looks striking and dark long before it is anywhere near ready.

The trick is to read the parts of the fruit the sun did not reach. The shoulders and top, exposed to light, turn a deep blue purple regardless of ripeness. That pigment develops from sun exposure rather than from ripening itself.

The base and interior are the real tell. Watch for that shaded area to shift from green toward a full, rich red. That color change follows the fruit’s actual ripening, the way it would on any red tomato.

Back that up with a gentle squeeze. A ripe fruit gives slightly, just like a ripe red tomato would. That holds true no matter how dark and dramatic its shoulders look.

What it tastes like

Anthocyanin tomatoes sometimes get written off as all looks and no flavor, and that reputation is not fair to this one. Growers consistently describe it as sweet, juicy, and genuinely good, not just a novelty.

That is a real compliment, since plenty of striking looking hybrids trade flavor for appearance. This variety manages to deliver both a dramatic color and a tomato worth actually eating.

It works well sliced fresh, where the purple and red interior makes for a striking plate. Its rich, sweet flavor also holds up fine in a salad or scattered into a colorful summer dish.

The real benefit behind the antioxidant marketing

Seed catalogs love to mention antioxidants when selling anthocyanin tomatoes, and the health claims attached to that word are usually overstated. Eating a purple tomato is not going to transform your health on its own.

There is a genuine, well documented benefit hiding behind the marketing, though, and it has nothing to do with human nutrition. Peer reviewed research on anthocyanin rich tomato skin found that fruit with this pigment keeps noticeably longer in storage than ordinary tomatoes.

The same research found these tomatoes are less prone to a major post harvest mold, since the anthocyanin in the skin itself resists the fungus that usually causes rot. That is a genuinely useful trait for a home gardener with more ripe tomatoes than they can eat in a day or two.

So the honest pitch is not about superfood status. It is that this pigment quietly buys you a bit more time on the counter before a ripe tomato starts to spoil.

How to grow the Indigo Apple tomato, start to finish

Starting seeds

Start seeds indoors 6 to 8 weeks before your last frost. Sow a quarter inch deep in fresh seed starting mix, kept warm around 70 to 80°F.

Give strong light the moment they sprout so they stay stocky. Pot up at the first true leaves and feed at half strength.

Transplanting and spacing

Plant out after frost, once nights hold above 50°F. Harden the seedlings off over a week first, then bury two thirds of the stem for strong roots.

Space plants about 2 to 3 feet apart. This is a vigorous, tall growing vine that still stays reasonably well behaved for its size.

Soil and feeding

Grow it in rich, well drained soil at a pH near 6.2 to 6.8. Work compost and a balanced fertilizer into the planting hole, then feed lightly once fruit sets. Our guide to feeding tomatoes covers the timing.

Light and water

Give it full sun, at least 6 to 8 hours a day, since sun exposure is what actually drives the blue purple color. Shaded fruit tends to stay greener and less dramatic.

Water deeply and evenly, aiming for 1 to 2 inches a week at the base. Steady moisture guards against cracking and blossom end rot. Our guide to watering tomatoes covers the rhythm.

Support

This is a tall, vigorous vine that needs sturdy support from the start. A tall cage or trellis works well. Growers report it stays fairly well mannered compared with some other big indeterminate types. Our guide to supporting tomatoes lays out the options.

Growing in containers

This variety can grow well in a large container, since it is a manageable size for an indeterminate vine. Use at least a 15 gallon pot with a sturdy cage set at planting time.

Since sun exposure drives that dramatic purple color, place the container somewhere it gets full, unobstructed sun rather than a partly shaded corner. A bright patio or open deck works especially well. Our guide to growing tomatoes in pots covers the container basics.

Problems to watch

Misjudged ripeness. The dramatic purple shoulders can fool new growers into picking too early. Check the shaded base and interior color along with a gentle squeeze, not the shoulders alone.

Cracking. This variety resists it better than many heirlooms, but uneven watering can still split fruit. Keep moisture steady and mulch well, and see our tomato problem guide.

Blossom end rot. A dark, sunken patch on the fruit bottom, driven by uneven watering. Fix the watering rhythm rather than reaching for sprays.

Sunscald resistance is not immunity. This variety carries some natural resistance to sunscald. Very intense, sudden sun on an unshaded plant can still cause damage.

Harvest and storage

Pick each fruit once the shaded base and interior have turned a full red and the fruit gives slightly to a gentle squeeze. Do not rely on the blue purple shoulders alone, since they color up long before the fruit is truly ready.

Cut the stem rather than tugging, since a ripe fruit can bruise its dark, delicate skin if pulled roughly. A pair of small scissors or pruners makes this easy.

Store ripe fruit at room temperature rather than in the fridge, just as you would with any tomato grown for flavor. Cold storage dulls the sweetness and softens the texture in a way that undoes a lot of what makes this variety worth growing.

Saving seeds

Good news for anyone who wants to keep growing this exact tomato. Indigo Apple is open pollinated and stabilized, so saved seed grows true to type.

Scoop the seeds and gel from a fully ripe fruit into a jar with a little water. Ferment for 2 to 3 days, rinse, and dry them on a plate before storing.

Many generations of careful selection went into stabilizing this variety. Saving your own seed continues that same patient breeding tradition in your own garden.

Indigo Apple vs Indigo Rose vs Cherokee Purple

Against Indigo Rose, the original Jim Myers release, the two share that same anthocyanin pigment and blue purple shoulders. Indigo Rose is the founding variety of the whole trend. Indigo Apple is a later cross bred specifically for improved size and flavor.

Against Cherokee Purple, the comparison is really about two different kinds of purple. Cherokee Purple gets its color the old fashioned heirloom way. Indigo Apple’s purple comes from anthocyanin, an entirely different pigment with a genuinely different origin story.

My honest take is simple. If you want to grow a real piece of tomato breeding history with genuinely good flavor attached, Indigo Apple earns its place.

The verdict

The Indigo Apple tomato is a striking, genuinely tasty result of one of the more interesting stories in modern tomato breeding. It carries a pigment that did not exist in garden tomatoes at all. A university program spent a decade coaxing it out of wild relatives before it reached a seed packet.

It asks for full sun to develop its best color, and a careful eye on the shaded parts of the fruit to judge ripeness correctly. In return, it delivers a sweet, juicy tomato unlike anything else in the garden.

Grow it for the color, and stay for the flavor. This is a tomato with real science behind every fruit, not just a pretty face at the seed rack.