Gadenin日本語Get the appWater on a schedule set by the fruit
Chinese quince roots deeper than common quince and stands dry spells better than most garden fruit trees, but the fruit is enormous and mostly water, so a dry midsummer shows up directly in the crop. The pattern to watch is simple: fruit that stalls at the size of a hen's egg and stays green, leaves that yellow and drop from the inside of the tree in late summer, and a scent at picking that is faint rather than filling the room.
The window that matters runs from the end of flowering until the fruit stops enlarging, which in practice is most of the summer. Through that period an established tree wants the equivalent of one inch (25 mm) of water a week, counting rain. Deliver it as a single slow soak, ten to fifteen gallons (40-55 L) for a mature tree, spread across the whole root area out to the branch tips rather than tipped at the trunk. Daily sprinkling wets the mulch and nothing else.
Once the fruit has stopped swelling and begun to turn from green to yellow, ease off. Steady moderate moisture is what you want at that stage. A heavy soak after a dry fortnight, or a downpour on baked ground, splits skins and lets rot in at exactly the point when the fruit has all its value.
A tree in a large container is a different animal and needs water two or three times a week through summer, every day in heat, because the pot dries from all sides. Potted trees also want repotting or root pruning every three or four years in late dormancy, or they stall and the bark stops developing.
| Stage | Water | Sign you are behind |
|---|---|---|
| Bud break to flowering | Usually none needed | Buds drying without opening in a dry spring |
| Petal fall to midsummer | 1 in (25 mm) a week including rain | Fruitlets yellowing and dropping in numbers |
| Midsummer to first color | 1 in (25 mm) a week, no gaps | Fruit stalled small and hard; inner leaves yellow |
| Color change to picking | Ease off; keep it even | Split skins after rain on dry ground |
| Leaf fall to bud break | None | Standing water rotting roots over winter |
Feed very little, and never late
This is a tree that is far more often spoiled by feeding than by neglect. Pushed with nitrogen it makes long soft whips of two to three feet (60-90 cm) that carry no flower buds, and that soft sappy growth is the exact tissue fireblight enters through. A well-fed Chinese quince is a tree that flowers thinly and then loses shoots to blight, which is a bad trade for a bag of fertilizer.
On ordinary soil with an annual mulch, an established tree needs nothing at all. On thin, sandy or exhausted ground, one light dressing of a balanced general fertilizer in early spring, around two ounces per square yard (70 g per square meter) over the root area and watered in, covers the whole year. Stop there. Nothing goes on after midsummer, because late nitrogen produces growth that has not hardened by the first frosts and dies back over winter.
Judge by extension growth instead of by a calendar. Shoots of eight to eighteen inches (20-45 cm) on a mature tree in a season are right. Under six inches (15 cm) consistently means the tree is short of water, light or root room. Over two feet (60 cm) consistently means it is being fed too well, or pruned too hard, and you should do less of both.
Look after the trunk, because that is the point of the tree
The flaking patchwork bark is the single best thing about Chinese quince and it is easy to damage without meaning to. The flakes lift naturally from about the fourth or fifth year and fall off through summer, exposing fresh green and orange beneath. Leave them entirely alone. Do not peel flakes that are still attached, do not scrub the trunk, do not use a wire brush, and do not paint or wrap the trunk against frost. Every one of those leaves a permanent scar in a surface that is meant to be looked at.
Keep grass and weeds away from the base with a mulched circle at least three feet (1 m) across, and take the same care with a mower or string trimmer that you would around a young tree, because a nick in this bark shows for a decade. Long grass against the trunk also keeps the bark damp, which dulls the color and encourages moss.
Lift the lower branches gradually as the tree grows so the trunk is visible from wherever people walk past. Do this over several winters, one or two branches a year, cutting cleanly back to the trunk collar without leaving stubs. A clean stem of four to six feet (1.2-1.8 m) is usually the most attractive result and makes picking and raking underneath far easier.
Do not treat surface algae, lichen or moss on the trunk as a problem. It is normal on any tree with slow-flaking bark, does no harm, and any attempt to scrub or wash it off will mark the bark far more than the growth ever would.
Thinning fruit, and managing the drop
The tree sets more fruit than it can finish and sheds the excess itself in early summer, within a few weeks of flowering. This is normal and needs no response. Once it has stopped, thin by hand to one fruit per cluster, leaving no more than one fruit for every twelve to eighteen inches (30-45 cm) of branch. On a mature garden tree that usually means a total of twenty to fifty fruit, which is more than enough for any household that steeps or preserves.
Thinning matters more here than on lighter-fruited trees because of sheer mass. Fifteen fruit at a pound and a half (700 g) each on one limb is over twenty pounds (9 kg) hanging on the end of a branch, and that is how a limb tears out in an autumn gale. Thinning also gives bigger, more evenly ripened, more strongly scented fruit, which is the entire reason to grow it.
Twist each unwanted fruit off with the fingers while it is still small rather than pulling, and take off anything already scarred, lopsided or rubbing against a branch. Marked fruit never steeps well because the flesh browns around the injury, so removing it early costs you nothing.
- Late winter Prune lightly while dormant, rake and remove any remaining leaf litter, renew the mulch out to the branch tips and check the stake ties before the spring winds.
- Spring, at flowering Record the date the first flower opens. Do not spray while bees are working. Feed once now if the soil is genuinely thin, and not otherwise.
- Early summer Let the natural drop happen without reacting to it. When it finishes, thin to one fruit per cluster, then begin the weekly deep soak if rain is short.
- Midsummer Keep watering. Cut out any shoot that has wilted and blackened at the tip and remove it from the garden. Stop feeding entirely from this point.
- Autumn Pick as fruit turns even yellow and the scent carries. Clear fallen leaves and any fruit left on the ground, then leave the trunk alone all winter.