Source: Wikimedia Commons
Satsuki azalea 'Kozan'
IntermediateRhododendron indicum 'Kozan'
An old satsuki of unknown parentage grown since before the Meiji era, with small, pale salmon-pink single flowers. Its slightly narrow small leaves, good branching and vigorous budding make it easy to train as bonsai.
About
Kozan is a satsuki azalea cultivar, one of the old varieties of unknown parentage. 'Satsuki' covers the Japanese native Rhododendron indicum together with related species and more than 2,000 cultivars. Kozan is said to have been grown since before the Meiji era. Cultivar descriptions give its flowers as a single pale salmon (some describe pale pink), normal form and small size, with slightly narrow, small leaves. It is vigorous, branches well and buds freely, so a bonsai framework is easy to build. Sports and crosses of Kozan are called the Kozan line, the sport 'Nikko' being well known, and many fine specimen trees are Kozan. Small, pale, single flowers with small leaves are the identifiers; the equally old 'Osakazuki' ('Taihai') has larger, deeper pink-purple flowers. Satsuki readily produce sports, so Kozan-line plants may bear differing flowers—confirm by the flowers as well as the label. A common basic cultivar, it is sold from starter material to finished bonsai.
Basic Info
Origin
Japan (an old satsuki cultivar of unknown parentage)
Lifespan
Little data for the cultivar (many old specimen trees exist)
Size
Grown as bonsai from shohin to large sizes
Temperature
-5〜35℃
Watering & Fertilizer
Fertilizer (April, June after flowering, Sept–Oct)
Growing Tips
Light & placement
Likes light, but summer sun scorches leaves and roots. Give young plants full sun; keep finished trees in part shade, always with good airflow
Watering
Likes water but its fine roots rot if waterlogged: 1–2 times daily in spring, 2–3 in summer, every 2–3 days in winter. Avoid watering in the midday heat
Temperature & overwintering
Reasonably hardy but dislikes cold winter wind; keep the pot from freezing under eaves or similar
Soil & repotting
Coarse, acidic kanuma-based mix. Repot right after flowering (June) or in autumn (late Sep–early Oct); protect autumn-repotted plants carefully in winter
Fertilizer
Solid fertilizer about April as new leaves harden, after flowering in June, and monthly in Sep–Oct. Underfeeding causes dieback
Pruning & styling
Flower buds form in July to mid-August, so finish pinching and pruning in June (early July west of Kanto). Wire in April and Sep–Oct
Pests & cautions
Especially pest-prone: lace bugs, spider mites, aphids and thrips are common, so regular control is needed in the growing season
Satsuki azalea 'Kozan' FAQ
QWhat is the growing difficulty level for Satsuki azalea 'Kozan'?
Intermediate. A variety suitable for intermediate growers. Requires some cultivation experience and knowledge of environment management. Pay careful attention to temperature and humidity control.
QHow should I water and fertilize Satsuki azalea 'Kozan'?
Satsuki azalea 'Kozan': watering & fertilizer — Fertilizer (April, June after flowering, Sept–Oct). Aim for appropriate frequency and amount.
QWhat is the typical price for Satsuki azalea 'Kozan'?
The price of Satsuki azalea 'Kozan' varies significantly by variety, characteristics, size, and lineage. Please check GrowerDirect's price guide for the latest market information.
Last updated: September 23, 2026
References & Sources
Edited & verified by: GrowerDirect Editorial Team
The classifications, regulations, and growing data on this page are created and verified based on the primary information database below.
Taxonomy & Authority
Regulations & Conservation Status
Not listed by CITES and not regulated for domestic sale. Not a registered variety under the Plant Variety Protection Act (no entry for 'Kozan' in the MAFF database, checked Sept 2026).
Sources: Species+ (CITES listing search) / MAFF Plant Variety Registration Database
Regulations may change. Always verify the latest information with the relevant authorities.
Related Species
Find listings for this species
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