Clematis akaishi

Clematis ‘Akaishi’

Categories: purple clematis varieties, pink clematis, 2 pruning group, large-flowered

‘Akaishi’ is a variety of clematis from the group of early-flowering large-flowered clematis. This variety is a Japanese selection, but it is sufficiently frost-tolerant and can be grown in Michigan, Wisconsin and other northern states of the USA. In the UK, France, and US states with not very cold winters you will have no problems with this clematis, except perhaps for flower burnout in bright sun.

The clematis variety ‘Akaishi’ was created in Japan, probably by specialists of the company ‘Sakata no Tane’ and registered in 1996. It turned out to be quite winter-hardy and relatively unpretentious, and this made it quite popular with novice gardeners.

Table of Contents


Group Early-flowering Large-flowered
Pruning Group 2 (light pruning)
Height 8.2-9.8 feet (2.5-3 meters)
Blooming May-June, reblooms in September
Flowers Large, up to 5.9 inches (15 cm) in diameter
Flower Color Purple edge of the sepals, red center
Hardiness Zones 4-9
Container Growing Yes


Clematis ‘Akaishi’ forms shoots up to 3 meters long with light green triple leaves. The shoots can be twisted on natural supports, wooden lattices or natural rope netting. Flowering begins in mid-May and continues until the end of June, re-flowering in September. Flowers are flat, large, up to 15 cm across. The sepals are 8, they have a slightly wavy edge and an elongated tip. The coloration of the sepals is purple with a red stripe in the middle. Stamen filaments are cream-colored, anthers are purple.

Clematis ‘Akaishi’ pictures

Clematis ‘Akaishi’ planting and care

Growing Clematis ‘Akaishi’ will not be difficult if you are in a region with more or less warm summers and not too cold winters. It will only be difficult in states such as Wisconsin, Michigan, Minnesota, South Dakota and colder states. In such states, when growing Clematis ‘Akaishi’ you will need to carefully cover last year’s shoots to preserve them until spring.

When to plant clematis ‘Akaishi’?

In states where there are four distinct seasons, it is best to plant clematis in late summer when the soil temperature drops to about 68 degrees Fahrenheit, or in spring when the soil temperature warms to that temperature. I find that clematis are best planted in the fall.

The most unfortunate time to plant clematis is in the summer when the clematis vines are growing vigorously with both roots and above ground parts. When transplanting at this time, you are sure to damage the roots and possibly also the stems. Therefore, you can only transplant the clematis liana from the pot into the open ground with a clump of soil.

Choosing where to plant

Choosing where to plant ‘Akaishi’ clematis depends on the climate in your area. If you have moderately hot summers and cool winters, it is best to choose the western, northern, eastern or southern side of a wall or fence so that the clematis is protected from the northern winds and is well exposed to the sun. At the same time, it is desirable that in the midday summer hours it should be slightly closed from the sun and be in semi-shade. This is necessary so that the clematis flowers burn out less in the bright sun.

If you are in a southern state or region, such as California, Texas, Florida and so on, it is better to plant Akaishi clematis near a north, east or west wall to reduce the chance of sunburn and soil overheating. Clematis in general tolerate overheating root systems very poorly, and their flowers are quite prone to burnout in the southern sun.

Planting soil

The soil for planting clematis should be loose, well cultivated, with a high humus content. Clematis can grow in neutral, slightly acidic and slightly alkaline soil, but it is believed that in slightly alkaline soil clematis is less likely to be affected by soil fungi that cause clematis wilt, which is the most dangerous disease.

Preparing the planting hole

Planting hole for clematis

I strongly advise you to prepare a large enough planting hole with a diameter of at least 1.5 feet and the same depth. This is important because for the first few years, the clematis root system will only develop inside this hole. To fill the hole, I always use the same soil that I extract from it, mixing it with compost and humus. To this mixture I also add about 20-30 grams of superphosphate and 20-30 grams of potassium sulfate to ensure good mineral nutrition in the first year. You can also use a prolonged complex fertilizer, but they cost a little more.

How to plant сlematis ‘Akaishi’

If you have an adult plant that has the lower part of the stems woody, you can plant it by burying it 2 or 3 buds deep so that the clematis branches out from the ground. This will make the plant more dense. If you have a young plant whose stems are green underneath, you should not bury it, as this can lead to soil fungi attacking the stems. Plant it as it is, leaving the entire above-ground part above ground. Perhaps you can transplant it deeper in a year or two.

Immediately after planting the clematis should be abundantly watered, so that the earth adheres to the roots. You can then leave it alone for a while.

Care of clematis ‘Akaishi’


Water ‘Akaishi’ clematis only in severe drought. Water infrequently but plenty at once, pouring about 2-3 gallons of water under mature plants and 1-1.5 gallons of water under young plants. Frequent and low volume watering is dangerous for clematis because it can lead to root rot.

Mulching the soil

Mulching the soil is a very good technique for growing clematis and protects the soil from overheating and excessive moisture evaporation. Mulch prevents weeds from germinating and is an additional source of organic matter for the soil.

I use freshly cut grass as mulch, hay or straw, if I can get it, are also good options. However, I never press the mulch close to the stem of the plant to avoid rotting or overheating due to the intense bacterial growth in the fresh grass. Around the stem itself, I sprinkle the soil with a mixture of sand and ash to slightly reduce the likelihood of clematis wilt developing.

Fertilizing the clematis

In the first year after planting I either don’t feed clematis at all or apply 5g of nitrogen fertilizer at the beginning of the growing season to speed up and enhance leaf growth a little. The rapid growth of the above-ground part will allow the clematis ‘Akaishi’ to also quickly develop a good root system during the first year.

Starting from the second year, I advise to feed clematis ‘Akaishi’ according to the following scheme.

  1. At the beginning of vegetation, apply 10 g of complex organic fertilizer, just scattering it around the plant on the soil surface. This can be compost or humus. In addition, introduce mineral fertilizer in the form of a solution, which should include 10 g of nitrogen, 5 g of phosphorus and 5 g of potassium by active substance. This is the dosage for an adult large plant. If you have a young plant, the rate of fertilizer should be reduced by half.
  2. The second feeding is carried out at the beginning of budding. I have a Clematis ‘Akaishi’ that buds in June. Introduce 5 g of phosphorus, 5 g of nitrogen and 5 g of potassium in the form of a solution under the root. It is also highly desirable to introduce a complex of micro- and macronutrients, from zinc to manganese. This will ensure a more abundant and strong flowering.
  3. The third feeding is carried out at the height of the first flowering, usually 2 or 3 weeks after the second feeding. Its dosage is the same: 5 g of nitrogen, 5 g of phosphorus and 5 g of potassium per adult plant.
  4. The fourth top dressing is carried out in late summer at the height of the second flowering of clematis ‘Akaishi’. This is the last major fertilization of the season, apply 5 g phosphorus and 5 g potassium to help the plant flower better and prepare for winter.

How to prune clematis ‘Akaishi’?

Clematis ‘Akaishi’ belongs to the second pruning group. This means that you need to save last year’s shoots until spring. The correct way to prune it is as follows:

  1. In summer, when the flowering on last year’s shoots is over, cut off the part of the shoot on which the flowering is over, and leave the lower part. The shoots of the current year, which have not yet flowered, in the summer do not touch.
  2. In the fall, when the current year’s shoots have finished flowering, cut them back to a height of about 3-4 feet (90-120 cm) cm above a pair of strong buds.

These shoots should, with the onset of cold days, be placed on the ground, pinned down and covered to protect them from frost. Of course, if there are no frosts in your region, there is no need to cover. The difficulty of covering depends on how cold it is in your region. If the winter is not very cold, it can be enough just to pour a bucket of dry peat on the tillering node. If the winter is cold, it is worth building a shelter of covering material and film, which will protect the entire shelter from moisture from the side, necessarily leaving a vent for the removal of excess water vapor. As a rule, clematis in this form perfectly winter and bloom on the shoots of the previous year the following spring.

Diseases and pests of clematis

Among the pests of clematis, none is of great importance. Sometimes clematis can be damaged by slugs, but this is extremely minor. Sometimes aphids are found on clematis, but they also never seriously harm. Of the diseases, the most dangerous for clematis is clematis wilt, which is caused by soil fungi of the genera Fusarium, Verticillium and some others.

Clematis wilt

These fungi penetrate the stem and fill the vessels. The movement of sap through the vessels stops, the shoot does not receive water and quickly shrivels and withers. Such a shoot should be cut out immediately, because it is no longer possible to cure it. It is also almost impossible to fight soil fungi – it is normal that they always multiply. Therefore, in such cases you can only keep the soil in a slightly alkaline state, and when planting, wash the roots and cover them with a mixture of sand and ash to create a barrier to pathogenic fungi for a while.

Clematis ‘Akaishi’ Reviews

  • South Dakota: Clematis ‘Akaishi’ is a great clematis, but it and all the flowers that end up in the midday sun burn out to almost white pretty quickly. So I planted it in the shade, after which I started getting two very impressive blooms each year with brightly colored flowers.
  • Colorado: Clematis ‘Akaishi’ does not require special care, but it has to be prepared for wintering so that last year’s shoots overwintered well and did not freeze. The clematis is now 4 years old and bloomed profusely and impressively last season.
  • UK, Derby neighborhood. Clematis ‘Akaishi’ requires little care and overwinters well in UK conditions. It responds well to feeding with complex fertilizers, its pruning is rather difficult, but not more difficult than other clematis of pruning group 2.
  • Oregon, near Beaverton. Clematis ‘Akaishi’ grows in shade and generally does well, but it’s important to make sure it doesn’t get flooded because that can damage the roots.

If you have also grown clematis ‘Akaishi’ at your place, please write a review in the comments to the article. It will help other readers of the site to get useful information.

About the author

Fedor Fironov
Graduate of Plant Protection Faculty at GSAU. Main area of interest – clematis, peonies and perennials of Lamiaceae .

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