Maximum Yield USA May 2018 | Page 41

Climbing plants, though, are among the most innovative entrepreneurs of all. Why waste energy on producing woody lignin for self-supporting trunks, plus the deep roots to support it all, when you can just borrow your neighbor’s instead? Climbers evolved on the ground, where little light reaches. If they were to flower and fruit, they had to find a way to get up to that light. Their evolutionary breakthrough was to co-opt the larger, stronger trees they grew alongside instead of trying to compete with them. Climbing plants start by creeping about until they find something they can borrow for support. There’s evidence when they’re in this scrambling, horizontal stage, they grow away from the light, as they’re more likely to come across a tree trunk if they grow into the center of the forest than out of it. Once they hit something, this physical contact triggers chemical changes that completely alter the way the plants grow. Instead of growing sideways, they now start reaching up, against the direction of gravity. The stems may start twisting round or leaves may modify into tendrils that search out further supports to hitch it upwards. Once they scramble up and over neighboring plants for long enough and high enough, they eventually reach sunlight and can flower and fruit. It’s a form of parasitism and an incredibly efficient way of saving energy for the important stuff (the flowers and fruit they need to procreate). Luckily for us, those fruits are also some of the most delicious and nutritious you can grow. A good third of the crops we grow have evolved into climbing plants. They include peas, climbing beans, cucumbers, melons, mashua, grapes, kiwi fruit, and blackberries. You can exploit their natural inclina- tion to tuck themselves in just about anywhere and find a way to the light, meaning you can squeeze a climber into any garden or growing system. They’re the ultimate survivors. Pea tendrils are modified leaves. Other tendril climbers like grapes and passion fruits use shoots produced separately from their stems. Either way, tendrils are too delicate to grip a sturdy pole. They’re better trained onto slender structures like twiggy pea sticks or string mesh netting, though make sure the mesh is about five inches square or those waving tendrils won’t sense the gap. Larger tendril climbers like melons and cucumbers can be very vigorous, so a little editing helps them concentrate on quality as well as quantity of fruit. Pinch out the growing tips of melons when plants have four strong side shoots. Then, once four good fruits have formed on each stem, pinch out the ends. Pinch out cucumber side shoots two leaves beyond a female flower to encourage more side shoots and more fruits to form. “ A good third of the crops we grow have evolved into climbing plants. They include peas, climbing beans, cucumbers, melons, mashua, grapes, kiwi fruit, and blackberries.” TYPES OF CLIMBERS Not all climbing crops grow the same way and understanding the different habits they’ve evolved tells you a lot about the conditions they need to thrive. Tendril climbers Examples: Peas, cucumbers, melons Support with: Wide-gauge netting, pea sticks Some climbing plants send out delicate, tendril- like feelers to find potential supports. As soon as a cucumber or pea tendril touches something, it hooks on and winds itself in like a corkscrew, pulling the plant closer to the support and creating a spring that can bounce in windy conditions like a car’s suspension system. feature 41