Gadenin日本語Get the appThe four decisions that make the year
Most of what you do to a kiwi vine can be done a week early or a week late without consequence. Four things cannot. Pruning has to happen in the middle of dormancy or you get heavy bleeding. Frost protection has to be ready before bud break, because once shoots are out a single night decides the crop. Pollination has to happen during a bloom window that lasts about a week. And picking has to happen when the seeds go black, before hard frost.
If you have those four right, the rest of the year is genuinely undemanding. The vine is vigorous, drought-tolerant once established, and largely free of pests. The failures people report are nearly always a missed window rather than an ongoing neglect.
Dormancy: the main cut
With the leaves off, the whole structure is visible and this is the one time you can see what you are doing. Take out every cane that fruited last season, remove the tangles and coils, keep well-spaced one-year-old canes twelve to eighteen inches (30 to 45 cm) apart along the arms, tie them along the wires, and shorten each to eight to twelve buds. On an established vine you will remove half to three-quarters of last year's wood.
Do this well after leaf fall and clearly before buds begin to swell. Work in dry weather, disinfect your pruners, and carry the prunings away rather than leaving them under the vine. While you are there, check the ties on the trunk for anything cutting in, look over the structure for rot at the post bases or slack wires, and put the trunk wrap and cat guards back on young plants.
Spread compost over the root area now if the soil is poor. Keep it clear of the trunk itself.
Spring: bud break, frost and bloom
As buds swell, the vine becomes vulnerable and you become a weather watcher. Have row cover where you can reach it and use it on small vines on any night forecast to reach 30F (minus 1C) or below. Rub off shoots emerging on the trunk and at the head with your thumb while they are soft; that costs nothing now and is a sawing job later.
Feed lightly at bud break if growth was weak last year, spreading it wide over the root area rather than at the trunk, and never as a concentrated dose near the stem. Skip the feed on a vine that grew strongly; excess nitrogen buys you twenty feet of cane and no extra fruit.
Bloom comes in late spring on the current season's shoots. Walk the vines daily through that week. Note the first and last day each vine has open flowers, keep every spray off the plants, and hand pollinate if the male and female overlap poorly or if the weather is cold and wet. This one week is worth more attention than the rest of the year combined.
Summer: shorten, untangle and water deeply
Once the fruit has set, tip each fruiting shoot four to six leaves beyond the last fruit, and keep tipping the runners that are heading off the structure. Go through every three or four weeks removing coiled shoots, downward shoots into the fruiting zone and sprouts from the trunk. Leave enough leaf cover over the fruit to shade it, because exposed fruit and exposed young bark both scald.
Water matters more for kiwi than for most fruit, because the root system is shallow and the leaf area is enormous. In a dry spell an established vine wants a deep soak of fifteen to twenty gallons (55 to 75 liters) once a week rather than a daily sprinkle, and a mulch over the root area to hold it. Wilting in the afternoon heat that recovers by evening is normal; wilting that is still there in the morning is not, and if the soil is wet at the time, suspect the roots rather than the weather.
Thin the crop if the set is very heavy, taking off small and misshapen fruit and any doubles, so the remainder can size up. Stop feeding by midsummer; late nitrogen makes soft growth that will not harden before frost.
Autumn: test, pick, store
Growth stops and the fruit finishes accumulating sugar. From the point where the fruit has stopped getting bigger, start cutting one open every week or so and looking at the seeds. White or tan seeds mean wait. Uniformly black seeds mean ready, and a refractometer reading of 6.5 Brix or above confirms it.
Pick the whole crop before a hard freeze even if the seeds are only just darkening, because frozen fruit will not store. Snap each fruit off so the stalk stays on the vine, handle it like eggs, sort out anything damaged for immediate use, lay the rest in shallow trays and get them cold within a day. Kept near 32F (0C) and away from apples and bananas, the crop holds for months and you ripen it in small batches as you want it.
After harvest, take away fallen leaves and any mummified fruit, and leave the vine alone. Do not prune yet: wounds made in autumn while the vine is still active heal poorly, and the leaves that remain are still feeding the roots.
The season at a glance, and the first four years
A kiwi does not fruit quickly. A grafted plant typically flowers in its third or fourth year and gives a real crop in its fifth or sixth; a seedling can take seven and may turn out to be male. The first years are about building a single clean trunk to the wire, then two arms along it, and resisting the temptation to let it fruit before the framework exists.
| Season | Main job | Watch for |
|---|---|---|
| Middle of dormancy | Structural pruning, tie in replacement canes, check the structure | Do not leave it until buds swell or it bleeds |
| Late dormancy | Compost over the root area, cat guards and trunk wraps in place | Ties cutting into the trunk |
| Bud break | Light feed only if needed, rub off trunk shoots | Late frost, have row cover ready |
| Late spring, bloom week | Record bloom dates, hand pollinate, no sprays at all | Male and female not overlapping |
| Early summer | Tip fruiting shoots past the fruit, prune the male hard after it flowers | Shoots coiling around wires and each other |
| Midsummer | Deep weekly watering in drought, thin a heavy set, untangle | Morning wilt, sunscald on fruit and young bark |
| Late summer | Stop feeding, keep the canopy open | Soft late growth that will not harden |
| Autumn | Cut samples and check seed color, pick, cool, store | Hard freeze forecast on hanging fruit |
| After leaf fall | Clear debris, plan the winter cut | Ooze or sunken bark on trunk and arms |
In the first two or three years, remove any flowers that appear. Letting a young vine fruit before its trunk and arms are built slows the framework by a full season, and the few fruits are small.
Six dates worth writing down every year
Keep it short enough that you actually do it. Record the date you pruned, the date buds broke, the first and last day of bloom on each vine, the date you picked and the seed color at that point, and the weight of the crop. Add a line for anything unusual, such as a frost that took the shoots or a week of rain during bloom.
Three years of those six dates answer the questions that otherwise stay guesses: whether your male and female overlap, whether you are picking too early, whether your vine is getting later or earlier as it matures, and whether last winter's harder cut actually gave you better fruit. Nothing else about kiwi growing repays a notebook as well, because the feedback loop is a year long and memory does not survive it.