Most vegetable gardeners growing leafy vegetables will have heard the term ‘cut-and-come-again’. We prefer the term cut-and-grow-again, as it more accurately describes what happens. As a harvesting technique the term is often poorly understood, and many gardeners may not appreciate quite how useful the system is – especially if they have just a small piece of land.
Any vegetable that is picked for its leaves can be harvested under a cut-and-grow-again system. This includes vegetables that most people would not consider suitable, such as kales, cabbages and hearted lettuces, as well as those that have become associated with the system like leafy lettuces, oriental greens, chards and perpetual spinach.
All leafy vegetables have an active growing point at the centre of the plant. This is where all new leaves of the plant are produced. When harvesting a leafy vegetable, like a lettuce, a gardener must decide where to cut. A cut made at the base will remove the whole plant including the central growing point. This is a single harvest approach typical for cabbages and hearted lettuces. With the growing point gone, all that remains is a stump, and it is time to make space for the next crop.
But if that same gardener, poised over the crop with the knife, makes the cut just a little higher above the plant’s growing point that plant, be it a lettuce, cabbage or pak choi, will not die. Instead, the growing point goes on producing new leaves, and the plant will regrow. After a successful cut-and-grow-again harvest all the harvested leaves are loose, and the growing point is undisturbed. A close inspection of the remaining plant will reveal several tiny, immature but perfectly formed leaves, and right in the very centre the growing point. Undamaged by the harvest the growing point will continue to produce leaves, and with nothing to impede their growth the miniscule leaves will quickly grow into full-sized leaves. In good growing conditions a spinach, lettuce or parsley plant could have enough new green leaves to be harvested again within just a few weeks. With no work at all – no seed to sow or new plants to tend – there are more young, tender leaves ready to eat for another meal.
All this depends on the gardener not damaging the growing point so it helps to know exactly where that growing point is situated. How can that spot be identified? Quite literally it is at the centre of the plant, just above the point where the smallest leaves are attached. Normally this is quite close to the ground, but it does vary depending on the type of vegetable and its maturity.
It is easy to tell if a cut has been made too low: if any harvested leaves, even if its just the two smallest, are attached at their base then the growing point has been removed and the vegetable’s regrowth ability has been seriously impaired.
Frequency of cut-and-grow again harvests
There is no rule about how large the leaves can be or how often the leaves should be harvested under a cut-and-grow-again system, but there are some basic guidelines to help a gardener decide. A general rule-of-thumb is to let the vegetable develop a decent amount of leaf before taking a cut, but not to wait so long that the quality of the older leaves start to deteriorate.
Managing a bed
If managed well a cut-and-grow-again crop is highly efficient, continuously producing green leaves that are generally better quality and available over a longer harvest period than the same crop picked as individual plants. The trick is to start harvesting early, when the plants are still quite young. At the next, and each subsequent, harvest cut the neighbouring uncut plants, but do not be tempted to take more than is required.
All good things come to an end
Unfortunately, even the best things come to an end. Eventually, the growing tip stops producing leaves and switches from a vegetative to a flowering stage. When this happens the plant has become reproductive, and will start to ‘bolt’, i.e. leaf production has stopped, the stem will elongate and a flower will emerge. For more information on bolting click here.
The length of the vegetative stage depends on the vegetable. For instance parsley and perpetual spinach, which are biennials, will produce new leaves throughout a growing season, and will only start to flower after having gone through a winter. Other crops, such as lettuces, coriander, rocket and oriental leaves, which are annuals, have different triggers to becoming reproductive and will have a much shorter growing period.
To the gardener, the first visible sign of the flowering stage is when the vegetable starts to elongate. As soon as a gardener notices the first signs of bolting the game is up, and now is the time to sow another crop.
© Joy Michaud