How To Grow Tomatoes And Potatoes On The Same Plant
Tomato plants and potato plants are both members of the Solanaceae, or nightshade, family and can be grafted together to form what is cleverly referred to as a “pomato” plant or “ketchup and fries.” The effect is cherry tomatoes growing on the vine above ground and white potatoes forming the base of the same plant below ground.
History of the pomato
The first attempt to graft a tomato to a potato occurred at the Max Planck Institute for Developmental Biology in Germany in 1977. The institution was able to graft a healthy, viable plant but it produced neither potatoes nor tomatoes. In 1994, the Max Planck Institute for Plant Breeding Research in Cologne grafted a plant that produced potatoes and tomatoes.
A graft is different from a hybrid; grafts cannot be grown from seed and do not occur in nature. The two plants remain genetically separate. Their inter-reliance is a mutualistic adaptation that is only a result of the two plants being forced together in such a way that the two plants come to rely on each other for growth and nutrients.
The way that plant grafting works is that an incision in each plant’s stem. The plants are then strapped together. As the incisions heal, the plants become fused together so that the leaves of the potato can be removed and the tomato’s roots can be cut off. This leaves the leafy top of the tomato plant to sustain the potato roots. Grafting is most effective with two healthy plants with stems of similar diameters.