Tomatoes and temperature
Botanically speaking, the tomato you eat is a fruit. So are watermelon, green pepper, eggplant, cucumber, and squash. A "fruit" is any fleshy material covering a seed or seeds.
Horticulturally speaking, the tomato is a vegetable plant. Most fruits, from a horticulture perspective, are grown on a woody plant (apples, cherries, raspberries, oranges); the exception is strawberries.
In 1893, the United States Supreme Court ruled that the tomato was a "vegetable" and therefore subject to import taxes. The suit was brought by a consortium of growers who wanted it declared a vegetable to protect U.S. crop development and prices.
The botanical name for the tomato has changed several times. Its earliest name was Lycopersicon or literally, wolf peach. Once the tomato was placed in the Solanum (Solanaceae) family, the botanical name changed to Solanum lycopersicon. Today the tomato is known as Lycopersicon esculentum, literally "edible wolf peach".
Tomatoes belong to the same family (Solanaceae) as potatoes, peppers and eggplants. Lycopersicon esculentum (tomato) is a perennial plant in the tropics but in northern climates it is grown as an annual. Flowers are generally borne in clusters of 4 to 8 but small fruited types may have 30 to 50 flowers per cluster. The flowers are mainly self pollinated by the wind. The fruit has 2 to 18 locules (chambers or sections).
The tomato is a native of the Peru, Bolivia, and Ecuador area of the Andes Mountains. Its antiquity is uncertain in regard to cultivation but it was being cultivated prior to the arrival of the Europeans. It was not until the early 19th century that the tomato was considered suitable as a food crop in the northeastern United States.
Tomatoes and temperatureTomatoes respond well to warm temperatures. The minimum temperature for seed germination is 10°C with a maximum temperature of 35°C and an optimum range of 17°C to 20°C.
An optimum growth rate is obtained at 22°C with reductions occurring above 30°C and below 12°C. Fruit setting is inhibited above 30°C and below 16°C. Rough fruit (cat faced) results from growing temperatures below 16°C.
Root growth does not occur below 16°C.
Tomatoes require adequate, even moisture, particularly at flowering and during fruit set.
Tomatoes grow best in well drained soils that are well supplied with organic matter. Sandy soils are suited for the speedy production of fruit. Loam and clay loam soils promote slower development.
Shelter from wind is important.
The tomato, pepper, eggplant and potato are closely related. The tomato plant is occasionally grafted to the potato, resulting in a freak plant which may produce tubers below ground (potatoes) and tomatoes above. This odd plant is sometimes called the "potomato" or "pomato".
Teachers and students will find more information about tomato seeds on the Heinz web site.
Students in grades 8-10 can investigate some of the more recent research related to Tomatoes, nutrition and seed storage.
Some of the topics that may be of interest - and which are related to the curriculum - include: