Satsuki azalea 'Kinsai'
BeginnerRhododendron indicum 'Kinsai'
An old satsuki of unknown parentage whose red flowers split into narrow strap-like petals (saizaki form). Its fine small leaves colour well in autumn. Occasionally a normal five-petalled flower appears, and that branch is cut out at flowering.
About
Kinsai is a satsuki azalea cultivar, one of the old varieties of unknown parentage. 'Satsuki' covers the Japanese native Rhododendron indicum with related species and more than 2,000 cultivars. The Japan Satsuki Association describes Kinsai as plain red, with the saizaki form in which the flower splits into 5 to 12 or 13 narrow strap-like petals, small in size (another guide says medium), with fine small leaves that colour well in autumn, flowering mid-season. The split red flower is the identifier: it looks nothing like a normal satsuki bloom. Now and then a normal five-petalled flower appears, which growers call 'rappa' (trumpet) and dislike. A form bearing only normal flowers is called 'Kin-no-hana' by the Association and 'Kinka' by the Kanuma society; other named offshoots include the tiny-leaved 'Ko-kinsai' and a koshimino-flowered form sold under its own name. Plants sold as Kinsai can carry normal-flowered branches, so check in bloom. It is vigorous, rated a beginner-friendly standard, and is sold from young plants to trained bonsai.
Size of the Satsuki azalea 'Kinsai'
The Satsuki azalea 'Kinsai' grows to Satsuki is an evergreen shrub of about 0.5–1 m; as bonsai it is trained to suit the pot.
Basic Info
Origin
Japan (an old satsuki cultivar of unknown parentage)
Lifespan
Little data for the cultivar
Size
Satsuki is an evergreen shrub of about 0.5–1 m; as bonsai it is trained to suit the pot
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)
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
Pest-prone: watch for lace bugs, spider mites, aphids and thrips. If a normal-shaped flower ('rappa') appears, mark it and cut that branch out at its base
Satsuki azalea 'Kinsai' FAQ
QWhat is the growing difficulty level for Satsuki azalea 'Kinsai'?
Beginner. A variety suitable for beginners. No special equipment or experience is required—you can grow it without problems by setting up a basic cultivation environment.
QHow large does Satsuki azalea 'Kinsai' get?
The mature size of Satsuki azalea 'Kinsai' is Satsuki is an evergreen shrub of about 0.5–1 m; as bonsai it is trained to suit the pot. This may vary slightly depending on cultivation environment and individual differences.
QHow should I water and fertilize Satsuki azalea 'Kinsai'?
Satsuki azalea 'Kinsai': watering & fertilizer — Fertilizer (April, June after flowering, Sept–Oct). Aim for appropriate frequency and amount.
QWhat is the typical price for Satsuki azalea 'Kinsai'?
The price of Satsuki azalea 'Kinsai' 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 'Kinsai' 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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