September 12, 2012

So here are the long-awaited ‘Indigo Rose’ tomatoes. Gardening is about experimentation. When I saw this plant at the nursery last spring I decided to make it one of the six tomato plants I have room for in my vegetable garden.

'Indigo Rose’ is the first truly purple tomato coming from the breeding program at Oregon State University. which seeks to develop tomatoes high in antioxidants. Americans consume an average of 90 pounds of tomatoes annually prompting the addition of antioxidants. Read more about the the OSU 'Indigo Rose’ here and Purple Tomato FAQ’s here.

Anthocyanin pigments account for the purple color in 'Indigo Rose’ and the red, blue and purple colors in some fruits and vegetables.* Research on anthocyanins has intensified recently because of the potential health benefits. Anthocyanins may offer protection from cardiovascular damage and have anti-cancer, antioxidant and anti-inflammatory effects. Some studies show a role in vision improvement and diabetes prevention.  Time will tell. (See FAQ page for more information).

So while we eat about 90 pounds of tomatoes each year, we eat less than one pound of blueberries. Hence, the effort to place anthocyanins in the common tomato. As a dietitian, I recommend choosing red cabbage, plums, eggplant, berries and other red, blue and purple fruits and vegetables if you want to increase anthocyanins in your diet.* 'Indigo Rose’ is a novelty and actually quite beautiful but not your best dietary source of anthocyanins.

The purple pigment develops as the tomato is exposed to the sun. Portions shaded by leaves do not develop the anthocyanins. As the tomato ripens it becomes less purple and the green turns red. The flesh is red but the anthocyanins are primarily in the skin and outer flesh.

You can Google the reports of others on the taste of 'Indigo Rose.’ Many say it is disappointing and without good flavor. I did a taste test this week of all my tomatoes. Though 'Indigo Rose’ lacked the complexity of the black tomatoes and 'Cherokee Purple’ it was decent–comparable to many of the hybrids I’ve grown in the past. 

Will I grow 'Indigo Rose’ next year? Probably not. Did I wait and wait for these  tomatoes to ripen? Yes, up to a month once tomatoes reached their full size. Did it produce well? Yes, possibly the best yielding tomato this year. Did I enjoy the beautiful purple color and the graceful long clusters each time I walked by the plant? Definitely. And yes, the tomato is not a GMO variety.

*The vibrant color of red cabbage and the blue of blueberries come from anthocyanins. Common fruits rich in anthocyanins include blackberries, raspberries, plums, cherries, blood oranges, black grapes. Vegetables that are good source of anthocyanins include eggplant, red onion, radish, red lettuce, red-skinned and purple potatoes.