Issue: March 23, 1998

Tomato tree question

Hi! I have a question. Someone told me about a tomato tree. Is there such a tree as this?

The tomato tree or tree tomato is a plant in the tomato family but is not a tomato. Its scientific name is Cyphomandra betacea. The genus Cyphomandra includes about 29 other species, but only the species C. betacea is commonly grown for its fruit.

The tomato tree requires warm temperatures since it is from the tropics. It is native to Peru. Outside the tropics, it must be grown in a greenhouse. It takes one and one-half to two years to become large enough to produce fruit. It needs a deep, fertile soil. However, I have seen it growing in a large pot in a greenhouse. In a pot, it might not reach its maximum potential size of over 10 feet.

The fruit is orange-red, egg shaped, and about two inches long. The fruit may be eaten uncooked but is most commonly stewed or made into jelly. My reference did not describe its flavor.

I have noticed that the plant has an unpleasant odor when you bruise or break the leaves and stems. Many plants in the Solanaceae, or tomato family, contain poisons in the parts of the plant which are not eaten. So, if you decide to grow the plant, eat only the fruit. I found no information about poisons, but caution is wise.

Applying manure and compost to the spring garden

I read that I should put manure on my garden in the fall. I was busy last fall and did not get around to spreading and turning in the manure and compost. Is it too late to put manure or compost on my garden now?

The reason we recommend applying manure to the garden in the fall is to allow the winter precipitation, which was plentiful this winter in much of New Mexico, to leach the salts from the manure deep into the soil so that our vegetables and flowers are not injured. Our soils are naturally salty, our water contains minerals, and the manure contains considerable quantities of salts. Excess salt is harmful to plants. Leaching to remove the salts reduces the chance of injury.

However, properly matured compost will have been properly leached in the frequent turning and application of water necessary for composting here in New Mexico. Even if compost were a major constituent, the composting process should have caused much of the harmful salts to be leached away. Compost often has considerable plant debris in addition to the manure, or no manure at all. In such a compost, there would definitely be no problem. You can apply well-matured compost to your garden now.

There are some commercial composts to consider with caution. These are good produces but may have high salt levels. Also, be wary of composts with high nitrogen levels. The nitrogen, while useful as a plant nutrient which is often deficient in New Mexico, can burn plants if the high nitrogen compost is applied in too great a quantity to the garden in the spring. You can use these commercially produced and sold composts - just don't overdo it.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!