Grafting plants is hard work: It helps reduce stress on plants’ roots and create sturdier crops, but it can really stress out farmers. Humans have to struggle to cut plants just the right way and bind them together. That’s where a new robot comes in: With the help of steel “hands,” it turns plant grafting from tedious art into swift science.
Vegetable expert Richard Hassell and his team recently revealed a new robotic system that grafts more quickly and efficiently than a human ever could. They modified a Korean-manufactured robot to grab two plants, precisely slice the upper shoot of one and the root stock of the other, and clamp the two parts together so they can grow into a single plant.
Think of the robot as a high-tech plant surgeon that makes precise slices and fuses together two organisms into a Franken-plant in a flash. In just an hour, the robot can graft together over 3,000 plants — a feat a human being could never accomplish.
“Generally, grafting is done by hand,” explained Hassell. “It’s a learned skill, so it’s very time-consuming.” Grafting thousands of plants can be grueling, and the sensitivity of young vegetable plants means there's a high failure rate. Imprecise or too-quick grafters can damage the plant, and the slow-and-steady can never hope to graft to scale.
That’s simply not viable for the increasing number of companies that rely on grafting to create hardier, more disease-resistant plants. Crops like peppers and tomatoes have delicate roots, so they can collapse once they’re put in the soil. Commercial operations fuse such plants with others that have hardier roots, like squash, so they can thrive beyond their earliest stages.
There are other upsides, too: Grafted plants need fewer fertilizers because they piggyback on plants that are already growing successfully. And once red plants like watermelons and tomatoes get new root systems, they produce even more lycopene — which gives them their bright color.
Grafting got its start in Asia millennia ago, and for the last several decades has been widely used to produce the continent’s commercial crops. But it’s been slower to catch on in the United States. Hassell thinks that's because it’s harder to find and pay laborers to learn the delicate technique.
Robotic laborers, on the other hand, require a higher one-time investment but yield endless bounties of precisely grafted plants. Once the metal gardener does its thing, plants are put into high-humidity chambers that promote the new graft to heal. In a week, they’re healthy enough to transfer to a greenhouse. A week later, they’ve adjusted to their newer, stronger roots and can be planted out in the field.
“Grafting is successful and it can improve the quality of the fruit that we devour,” said Hassell. Maybe it’s time to hang up the garden gloves and admit that our robot overlords are simply better gardeners than we could ever hope to be.