Gadenin日本語Get the appTwo different jobs, often confused
Pruning a winter melon means two separate things and it helps to keep them apart in your head. The first is shaping the vine early, which is about how many runners the plant carries and where the fruit will eventually sit. The second is thinning the fruit, which is about how much of the plant's capacity goes into each one. The first job takes ten minutes in early summer, the second takes two minutes at fruit set, and between them they decide the size and keeping quality of everything you harvest.
What pruning is not is a way to tidy the plant. Leaf area is the engine that fills a twenty pound (9 kg) fruit, and every healthy leaf you cut off for neatness is weight you will not harvest. Once the framework is set, cut almost nothing.
Pinching the main vine to force laterals
The main vine is not where the useful fruit comes from. Female flowers appear sparsely on the leader and much more freely on the side shoots, so the standard practice is to stop the leader early and let the plant put its energy into laterals instead. The result is three or four runners of similar vigor, each capable of carrying a fruit, rather than one dominant vine trailing away across the plot.
Do this while the plant is small. Pinching a leader that is already twelve feet (3.6 m) long achieves nothing except a large wound and a fortnight of sulking.
- Count to the fifth or sixth leaf When the main vine has five or six true leaves and is beginning to run, pinch out the growing tip with your fingers. Do it in dry weather so the wound seals rather than sitting wet.
- Let the laterals come Within one to two weeks, side shoots will break from the leaf axils. Let them all start, then select once you can see which are strongest.
- Keep three or four runners Choose the three or four most vigorous laterals and rub the rest out at the base. Space the keepers around the plant so they run outwards rather than over each other.
- Stop pruning once they run From the point the chosen runners are away, leave the plant alone apart from fruit thinning and removing dead leaves. Late tip-pinching just costs you leaf.
In a short season some growers skip the pinch entirely and let the leader run, on the grounds that any delay is unaffordable. That is a legitimate trade-off. What you must not do is pinch late, which combines the delay with none of the benefit.
Thinning the fruit is the decision that matters
A well-grown plant will try to set far more fruit than it can finish. It is not doing this because it can support them; it is hedging, and if you leave it to its own devices you get a crop of undersized fruit with thin skin and poor keeping quality. Restricting each plant to one or two fruit is the single most effective thing you do all season.
Choose early. A fruit that has already spent three weeks growing has consumed resources you cannot get back, so make the call as soon as you can tell which fruit have set properly and are swelling evenly.
| Fruit to keep | Which one | When to decide |
|---|---|---|
| First choice | The earliest fruit that is swelling evenly | About a week after it sets |
| Second choice | A fruit on a different runner, well spaced | At the same time |
| Remove | Anything misshapen, yellowing or lopsided | As soon as you notice |
| Remove | Any fruit set after your keepers are fist-sized | Weekly, as they appear |
Cut unwanted fruit off with snips rather than pulling. Tearing a young fruit away damages the stem it was attached to, and that runner may then fail to carry the fruit you actually wanted.
Leaves: what to remove and what to leave
By late summer a winter melon plant looks a mess, with yellowing lower leaves, mildewed patches and a good deal of dead material underneath. The instinct to clear it out is mostly wrong. Leaves that are more than half dead or heavily mildewed can go, because they are contributing nothing and holding moisture; anything still substantially green is doing work.
The one place to be a little more willing is directly around a maturing fruit sitting on damp ground. Opening the canopy slightly there improves airflow under the fruit and reduces the chance of rot at the contact point, without costing much leaf area.
| Leaf condition | Action | Reason |
|---|---|---|
| More than half yellow or dead | Remove and take off the plot | No longer feeding, holds damp |
| Heavily mildewed, over half covered | Remove | Source of spores, little photosynthesis left |
| Lightly mildewed | Leave it | Still working, removal costs more than it saves |
| Green leaves shading a fruit | Leave them | Shade prevents skin scald on the shoulder |
| Dense leaf sitting on a fruit | Lift or thin slightly | Airflow at the contact point |
Stopping the plant at the end of the season
About five or six weeks before your expected first frost, the plant is best stopped. Any fruit setting after that point has no chance of finishing, and everything it takes is subtracted from the fruit you are counting on. Pinch out the tip of each runner and remove every flower and small fruit as they appear from then on.
This is worth doing even if the plant looks vigorous. A late flush of growth in autumn is the plant responding to shortening days, not evidence that there is time left.
- Count back from your first frost Winter melon needs roughly six weeks from set to a fruit worth keeping. Anything setting inside that window comes to nothing, so stop the plant when you reach it.
- Pinch every runner tip Take the growing point off each of the three or four main runners on the same day. Doing them one at a time over a fortnight defeats the purpose.
- Strip late flowers weekly Go over the plant once a week and remove new flowers and any fruit smaller than your fist. It takes two minutes and it all goes into the keepers.
What to record
Pruning decisions are made once a year on a plant you will not see again for twelve months, so the record is what carries the learning forward. Three short notes are enough to improve the following season.
- The date and leaf count when you pinched Note how many leaves the vine had when you stopped it and how long the laterals took to break. That tells you whether to pinch earlier or later next time.
- How many runners and how many fruit Record both numbers alongside the final fruit weights. This is the comparison that eventually settles how hard to thin on your soil.
- The date you stopped the plant Write down when you pinched the runner tips and whether any fruit set after that date actually finished. If several did, you stopped a week too early.