Kiwi Super Issai Plant – A Self-Fertile Hardy Kiwi Berry Plant for UK Gardens
Options Explained:
12 Litre: Supplied in a 12 Litre pot, 2-3 years old, 90-200cm tall (depends what time of year you buy)
Kiwi Super Issai is a self-fertile hardy kiwi plant and is ideal for those wanting small, sweet kiwi fruits from a small footprint of land. This is because everything needed for a fruit crop is on one plant i.e. male and female flowers. Many kiwi plants need a pollination partner, i.e. a second kiwi to produce fruits, which means more space, more maintenance and more to go wrong if one plant struggles or dies.
Although often searched for as a kiwi tree, Super Issai is actually a vigorous deciduous climbing vine and needs some means of support such as a trellis, wire support, arch, pergola, fence or sunny wall. With a fast growth rate, if you stand still talking to the neighbours long enough, it might start climbing you. Expect a fully mature height and spread of 4m as early as 5 years old.
Super Issai belongs to the hardy kiwi / kiwi berry group, not the large fuzzy supermarket kiwi group. The fruits are small, smooth-skinned, juicy, sweeter than normal kiwi and can be eaten whole like grapes including the skin.
The plant has attractive green foliage, small creamy-white flowers and a useful leafy climbing habit, so it is not just a fruiting plant. It can also be used as an ornamental climber to soften a wall, cover a pergola, train along wires or add edible interest to a sunny garden space.
Expect fruit crops from Super Issai around August, but weather can bring that backward or forward by a month. If fruit does not fully ripen outdoors, kiwi fruit can be picked and ripened indoors.
Kiwi Super Issai Plant Pot Sizes – P9 vs 3L vs 12L
A smaller and cheaper P9 pot can look good value, but with Kiwi Super Issai you still have to wait for the plant to build size, root strength and fruiting framework before fruiting. Kiwis fruit on average at 3-4 years old. A P9 pot will be less than a year old and a 2-3L pot will be in the 1-2 year old range. This means you have to wait a minimum of 1-2 years for a full crop of kiwis.
With a 12L pot, you are buying an older, more hardy kiwi plant with a better-developed root system, stronger stems, more stored energy and more immediate framework to train onto wires, a pergola, trellis or wall support and should fruit the same year of purchase (depends when you buy it)
Planting, Care and Maintenance for Kiwi Super Issai
Plant Kiwi Super Issai in a warm, sunny, sheltered position with fertile, moist but well-drained soil, preferably against a south-facing or west-facing wall. Hardy kiwis can also be grown in open ground in milder areas, but shelter is still important because young shoots can be vulnerable to late frost damage.
Give the plant strong support before it starts making serious growth. Horizontal wires, trellis, pergolas, arbours, arches and sturdy fence or wall systems can all work, but the support must be strong enough for a vigorous mature vine. Train the main stems onto the support while they are young and flexible rather than letting the plant tangle itself first.
Water well after planting and keep the soil evenly moist while the plant establishes, especially during dry spells. RHS advises watering newly planted kiwi plants during the growing season for at least the first few years after planting. Once established, they should not usually need constant watering, but watering during prolonged dry spells while fruit is swelling can help support the crop.
Pruning is important because Super Issai is a climbing fruiting vine, not a neat little bush. RHS says kiwis are best pruned twice a year, in summer and winter, to keep vigorous growth controlled and encourage good fruiting. Train a permanent framework, then manage new growth so the plant stays open, supported and productive i.e. let light and air into it.
Interesting Facts About Kiwi Super Issai
The word "issai" in Japanese can mean "nothing" or "one year old" depending on how it is used. Several anecdotal websites claim the variety is Japanese, and the name reflects the early cropping abilities from the first year of planting.
It is an ideal plant for people who like vines, not Jeremy on radio two or his brother Tim on yet another reality TV show, but gardeners who like to train them over structures.
Quick Fruit Tree Links
Take a look at our TOP SELLING FRUIT TREES, Wet ground issues then choose a PEAR TREE first, followed by APPLE TREES. For more information on pollination please look at choosing the CORRECT POLLINATION PARTNER
Fruit Tree Life Expectancy
Most fruit trees will give you AT LEAST 40 years of fruit. Pears can go to 70. Records of 200 year old trees exist but this is the exception, not the rule.
Do I Need To Stake My Bare Root Fruit Tree?
Most of the time, the answer will be no, especially if under 200cm tall. However our article on Tree Staking should help guide you.
Planting In The Corner Of A Garden
Air and light is reduced in this location which could promote fungus and bacterial issues. Corners of houses and fences can also suffer leeching issues so we advise against it.
General Kiwi Plant Information
Although Kiwis are quite forgiving (good candidates for working on the Samaritans Help Line?) in terms of temperature preference, best results will be gained by planting them in full sun with shelter e.g. a garden with fences to keep the high winds off. Although they will tolerate less than perfect soils, a deep sandy loam is preferable but try to keep them out of clay.
Newly transplanted Kiwi plants should be watered every day until you are sure they have taken hold. Evidence of this could be new shoots or visible growth.
A kiwi plant will need 240 frost free days to perform well so if you are in less than perfect conditions, under glass or polythene will be your safest bet. A general rule of thumb is that if peaches, almonds and citrus are growing in your area then kiwi will be fine also.
On the flip side, if the winter is not cold enough, the kiwi may fail to loose all its leaves and will then fail to flower.
The easiest and arguably the best place to plant a kiwi fruit is along a trellis or some other form of support. An overhead trellis is perfect as the fruits will drop making them easier to harvest.
For the purists out there, an acidic soil of 5 to 6.5 will yield best results along with lots of organic matter and not too high in salt. If the soil is lacking, the leaves will show nitrogen deficiency. This will be evident by pale green or yellow leaves on the older leaves and poor growth. The older leaves show first as the plant will move nitrogen from the older leaves to protect the newer ones. Adding too much carbon to the soil e.g. sawdust can cause this problem as the soil organisms use the nitrogen to break down the carbon. A quick fix is to mulch with grass clippings or use a fertilizer high in nitrogen. A longer fix is to build organic matter up in the soil or use green manure techniques such as planting red or white clover.
If the leaves turn brown and fall off, especially in the summer, this could be a sign of insufficient watering.
Kiwi vines are quite nitrogen hungry especially early in the season. If you are going to feed them, do this around March time.
Mulching is recommended but don't let it come into contact with the vine. Do this in mid-spring and make it at least 3 inches deep. This will suppress weeds, retain soil moisture and help keep the root system cool.
If you catch your cat rubbing your kiwi or digging at the root, it is because there is a scent coming from the tree that is similar to catnip.
Unknown Kiwi sex
If you have a single kiwi fruit vine that is not producing fruits then you have a male or female vine and require the opposite sex planted nearby. To establish which sex you have, look at the blossom. Female flowers will have a pure white star shaped stigma. This is the central part of the flower and looks like thick hairs. The male flower will have a central section that also looks like thick hairs but they will be yellow or orange in colour.
Kiwi Fruits
Some chefs use kiwi fruit to tenderise meat as there is an enzyme in the fruits that makes meat softer.
Most kiwi fruits are high in Vitamins A,C and E along with potassium and the seeds are high in ALA (part of omega 3 fatty acid)
You can eat the skin of Kiwi fruits but it is an acquired taste. If you do not know where your kiwi came from e.g. the supermarket, then it is possible it has been sprayed and these chemicals will still be in the skin. The same problem occurs if you live close to a busy road, particulates from the engine exhaust could be in the skin regardless of the amount of washing. In these instances, best to peel. The benefit to eating the skin is that it contains flavonoids, insoluble fibre and anti-oxidants.
When you harvest the fruits, they might be quite hard. Finish ripening by putting into a bag of apples.
The fruits will last several months inside a plastic bag and chilled and will be ripe when the seeds are black.
Kiwi History
They were introduced to the West at the beginning of the 20th century when a missionary called Isabel Fraiser took them to New Zealand after visiting China. The seeds were planted in 1906 and the first kiwi fruits harvested in 1910. It took another 42 years to bring them to England when 13 tonnes of them were exported to us...nothing like a sense of urgency then.
Kiwi Pruning
Kiwi are a bit like teenagers. Leave them unsupervised and they take the easiest route. If you leave your Kiwi plant un-pruned, it will put its efforts into leaf and stem production rather than fruit.
If you are training it to climb a trellis, let it grow until it reaches the height you want it to be and then train the main stem to grow to the sides. Train side shoots to grow out horizontally as well and when they all get to the end of the frame, cut the tips. These will then be the permanent growing structure for your fruits. All new shoots that then come from this structure, prune back to 4-5 leaves. This then forces the vine to put its resources into blossoms and fruits.
As blossoms only grow on one year old wood or at the base of new shoots, your growing structure will soon become congested. The time to cut out the congested sections of your growing structure will be in the winter. It will look harsh but if you choose a section of the vine to do each season your losses will be minimal. You then train in a shoot to replace it.
In the summer, all the shoots that have fruit on them, remove the shoot past the fruit except 4-5 leaves. Once the fruit has been harvested, shorten the shoot to around 5-8 cm. This again forces the vine to put resources into the fruit and also lets in valuable heat and light.
