Deciduous Azalea Whitethroat AGM

Delightful small pure white double funnel-shaped flowers. Flowering in May - June this is a lovely neat compact plant with a spreading habit. It performs best in light dappled shade and has attractive silvery light green leaves. Height 120-150cm in 10 years.

• Recommended for pure white flowers.
• Easy to grow.
• Group:Deciduous Azalea (Knaphill hybrid).
• Parentage: unknown.
• Hybridization date: pre 1950 (before 1941).
• Bred by: Waterer (Knap Hill). Origin: British.
• Habit: compact and spreading.
• Ideal position: Dappled shade.
• Ideal soil: pH 4.5 to 6.
• RHS Hardiness Rating: H6.
• How we usually propagate this plant: Cutting.
• Awards: RHS Award of Garden Merit.

Customer Reviews

By Margaret Smith on 11th August 2022

"Another great azalea in superb condition. Planted now and seems happy with its dappled position. Always so well tended plants."

Good to know

From a botanical point of view, deciduous azaleas are part of the rhododendron family, but typically they only have 5-7 stamens in the flowers instead of 11-13 stamens present in other rhododendrons. They make a dazzling display, particularly in yellows, oranges and reds, but can also be very subtle in shades of pink and white. They are tough and fast growing plants typically reaching 125-150cm in 10 years. Our selection ranges from the discreet small flowered species and Ghent varieties, to the bold large flowering Knaphill and Exbury types. Many have the added value of a good scent in spring, and fiery autumn colours before leaf fall. Our newest introductions greatly extend the season into late June and July.

Deciduous azaleas have a stronger root system and will tolerate poorer conditions and a slightly higher pH than other rhododendrons. They can be grown in soils up to pH 6.5 when plenty of ericaceous compost is added. They prefer light dappled shade, but can also be grown in sun or more shade. In sun, the plants will be bushier and lower, with more flowers, but these will not last so long. In shade, the plants will be taller, with fewer flowers, but these will last longer.

All require good moist ericaceous soil with a high organic content. For a guide to plant spacing, use the height we give in 10 years as a guide to the distance between each plant, or approximately 1 plant per 1.5m². Plant no deeper than the top of the rootball, and dig in plenty of good ericaceous compost around the sides.  A teaspoon of slow release feed is sufficient for a 3 litre plant, rising to a small handful for a mature plant.  They are tough plants, and tolerate growing in containers, where their flowers, scent and autumn colours can be appreciated. Re-pot every 3 years for best performance.

Please note: Plants supplied in winter months can look quite bare and stick-like, and may be pruned back to encourage more branching. This is normal, and they will soon fill out in the spring.


For further advice, For further advice, see here

Size Guide

picture for example only

The Basics

Ideal soil

Acidic soil, good organic content, pH 4.5-6.0. Inkarho range of rhododendrons will tolerate soils up to pH7.5

Sun or Shade

Light dappled shade is best for most varieties.

Shelter

Refer to hardiness rating. Give young plants protection.

Site Selection

Avoid close to trees, roots, invasive weeds, walls, hot patios, dry banks and waterlogged soils. Do not use weed matting or stone mulch.

Plant spacing

Use the height shown in 10 years as a guide to the distance between each plant. Allow room for plant to fill out. If planting closer for instant impact, be prepared to move plants after a few years.

Compost

• 3 litre pot, dig in 10-20 litres of ericaceous compost.
• 7.5 litre pot, dig in 20-30 litres of ericaceous compost.
• 70-80cm specimen, dig in 60 litres of ericaceous compost.
• 100-120cm specimen, dig in 120 litres of ericaceous compost.

Planting depth

Plant high in the ground, with the top of the rootball visible.

Feeding

Slow-release ericaceous feed recommended in March and straight after flowering.

Mulch

Recommended every few years.

Water

The key ingredient! Keep moist all season, especially the critical time at end of June for flower bud initiation. Tap water is better than no water. Heavy dose at least once per week in dry weather.

Drainage

Ensure good drainage in winter, especially with yellow flowering varieties. Avoid waterlogged sites.

Pruning

Rhododendrons and Camellias: Not normally required. Tidy wayward shoots after flowering.

Evergreen azaleas and Bloombux can be clipped into a low hedge.

Magnolias and Acers: Formative pruning when young to shape into a tree or bush.

Deadheading

Remove old flower-heads, particularly on young or weak plants.

For further advice see here

Delivery & Returns

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