Botanical Overview
Actinidia chinensis var. deliciosa: Kiwifruit, is the best known plant in the Chinese
Gooseberry family (Actinidiaceae) which includes 3 genera and about 360 species,
Description
Form:
A woody, twining vine.
Lifespan:
50 years.
Leaf retention:
Deciduous.
Growth rate:
Moderate to rapid.
Mature Size:
30' long.
Flowers:
White changing to pale yellow, 5-6 petals, fragrant, lacking nectar, male and female on
separate plants, both sexes having many stamens but without pollen on the female. There
are cultivars with self-fruitful, bisexual flowers, but they fail in high summer
temperatures.
Bloom:
Spring, after leaf-out, or fall. These plants tend to bloom heavily and lightly in alternate
years, affecting fruit production.
Self-fruitful:
No. Both male and female plants need to be grown, in a ratio of 1 male to 6-10 females. The
male should be upwind if in a prevailing wind location.
Years before fruiting:
2-5. Full productivity occurs after 8-12 years.
Fruit:
The skin is tan and fuzzy and usually not eaten. Its flesh is green with small black seeds
and a pale yellow center. The entire fruit is edible on the best cultivars.
Months for fruit to ripen:
About 6. The fruit is mature when its seeds have turned black. One fruit must be picked and
cut open each week from the first week of October on, until the seeds have turned black.
Remove fruit of the same size when harvesting and save the smaller immature ones until later.
Do not wait until fruit have softened before harvesting. The fruit ripen off the vine.
Storage after harvest:
Refrigerated and placed in a vented plastic bag, hard kiwi can last 2 months. Fruit will
ripen at room temperature and become ready to eat when soft. Soft kiwi should be eaten within
2 days.
Leaves:
Green, round to nearly heart-shaped.
Stems:
Kiwifruit vine climbs by twining around supports. It has no thorns or tendrils.
Roots:
One-half of the total root mass stays within a 6-13' depth but some roots probably grow
deeper. Cultivars are grafted onto seedling rootstocks.
Cultivars of Note:
'Tomari' a male used to pollinate females.
'Vincent' a female with a low chill requirement.
Wildlife:
The flowers attract pollinating insects, but rarely bees or butterflies due to the lack
of nectar.
Toxic / Danger:
No.
Origin:
China.
Cultivation and Uses
USDA hardiness zones:
7-9.
Chill hours:
100-400, depending on cultivar.
Heat tolerant:
Temperatures over 85°F require over 50% part shade to near full all day open shade
and frequent water.
Drought tolerant:
No. Drooping leaves, browning of leaf margins, and leaf drop are symptoms of insufficient
water.
Sun:
This plant needs full sun during blooming or the crop size is greatly reduced. Part shade
during fruit development results in lower fruit quality but can be successful. Temperatures
over 85°F require part shade to full, open shade.
Planting:
This plant cannot be grown in a region with alkaline soil due to its root depth. In a hot,
dry region with neutral soil: [1] Locate the vines in an area that receives full sun which
can be switched to part shade in temperatures over 85°F, is sheltered from strong wind,
and has at least a 10' soil depth.
[2] Dig a garden trench 5' wide and 2' deep, allowing 10' of length for each vine (centered)
to avoid root competition for nutrients. For example, with two vines, the trench should be
20' long. [3] Fill the trench with well draining, highly organic, acidic soil. [4] Install
a strong trellis. [5] Plant the vines after the last frost date.
These plants do not grow well in containers.
Soil:
Well draining, 10' deep, high in organic content, pH 5.1-6.5 (strongly acidic to slightly
acidic). It will tolerate a soil pH of 6.6-7.3 (neutral), but becomes chlorotic above pH 6.0.
This plant is not salt tolerant and fares poorly in alkaline soil.
Fertilize:
Use an organic fertilizer, for acid-loving plants, late winter and early summer, spread up to
2.5' from the trunk. Avoid any fertilizer containing chloride, to which Kiwifruit are very
sensitive. An iron supplement is used to treat chlorosis.
Water after becoming established:
Deep water 2-3 times a week in the hottest part of year, especially when fruiting. Do not
allow soil to dry out.
Mulch:
Spread organic mulch in a 5' radius around, and 1' away from, the trunk, to reduce moisture
loss and protect the roots from temperature extremes.
Prune:
The vines must be supported with a strong trellis. One main stem is allowed to grow 6' high and
then sideways. Lateral shoots are cut back in winter after fruiting.
Litter:
Leaves in fall and fruit if not harvested.
Propagation:
Softwood cuttings, collected in July or August, treated with plant growth regulator IBA in
2000-6000 ppm concentration and rooted in full sunshine with automatic misters. Softwood
cuttings grafted onto seedling rootstock.
Uses:
Ornamental vine, edible fruit eaten raw. Slightly under-ripe fruit (high in pectin) are used
to make jams and jellies. It is also used to make wine, and as a meat tenderizer.
Comments
Its scientific synonym is Actinidia deliciosa.
This plant grows poorly in hot, dry regions with alkaline soil due to its preference
to grow very deep roots in acidic soil, and its dislike of high temperatures.
Do you have additional information or a different experience for these plants that you would
like to share? Email info@GardenOracle.com. All contributions are welcome and appreciated.