Trellising

Trellising is the practice of training vining or climbing plants, such as cucumbers, beans, peas or indeterminate tomatoes, to grow upward along a frame, netting or set of stakes instead of sprawling across the floor of a container or balcony. Because floor space is one of the most limited resources on a balcony, growing vertically lets a gardener fit far more plants into the same footprint.

A trellis also improves airflow around leaves, which can reduce fungal problems compared to a sprawling plant lying against damp soil or pavement, and it makes harvesting easier since fruit hangs at an accessible height rather than hiding under foliage on the ground. The structure itself needs to be anchored firmly to the container or fixed to a wall or railing, since a mature vine loaded with fruit catches wind like a sail.

When setting up a trellis, match its height and strength to the eventual size of the plant rather than how small the seedling looks at planting time, since an undersized support often fails partway through the season. A common mistake is trellising directly against a flimsy railing planter, which can tip or pull loose once the plant fills out and the wind picks up.