Evergreen Azalea Niagara AGM

Wonderful large white wavy edged flowers with a faint yellow green eye in the centre. Flowering in mid May, we think this is one of the best white flowered varieties. Dense bushy upright habit, and attractive pale green leaves. Height 60-80cm in 10 years.

• Ideal for small gardens and mixed borders.
• Easy to grow.
• Group:Evergreen Azalea (Glenn Dale hybrid).
• Parentage: 'Lilacinum' x 'Willy' (s) X 'Mrs Carmichael'
• Hybridization date: pre 1950 (1948).
• Bred by: B.Y. Morrison. Origin: American.
• Habit: Upright.
• Ideal position: Most garden situations.
• 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 Viv Johnson on 6th January 2025

"Awesome plants in excellent condition. Great delivery."

By Mary Cochrane on 1st January 2024

"This plant and the 'Canzonetta' arrived the next day which I found amazing! They were both for Christmas gifts and were fine, sturdy, healthy plants which were well received. All the plants I have received from Millais have been of the same excellent quality and swiftly dispatched."

By Mr mark Jones on 18th November 2023

"Quality plant as always from Millais"

By Ronnie Green on 10th November 2021

"I was thrilled with my plant - beautifully healthy. Packaging & delivery all excellent. Would definitely recommend. "

By mhudson on 6th November 2020

"Very hasppy with the service and the quality of the plants"

By MaggieKeegan on 14th October 2020

"Excellent service, beautiful condition "

By KerenLeivesley on 8th September 2020

"Delighted with the quality of the plant. It was delivered promptly and we'll packaged. Received lots of care instructions online as well."

Good to know

Evergreen Azaleas

From a botanical point of view, evergreen 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. Evergreen azaleas, sometimes known as Japanese azaleas, are as popular as ever, and are ideal for any size of garden from a window box to a large estate. Most azaleas grow to 60-75 cm in 10 years, but look out for our speciality nakaharae azaleas which are late flowering, prostrate, and excellent for cascading over walls or tubs.

Some of the first evergreen azaleas were introduced by Ernest Wilson (Wilson’s 50) from Japan at the beginning of the twentieth century. These small flowered varieties are full of character, best seen at the Isabella Plantation in Richmond Park where they look delightful. However, these early plants are not as hardy as modern varieties such as those bred in Northern Germany. Other breeders, particularly in America, have concentrated on breeding larger flowers which can certainly look impressive. When buying plants, consider the hardiness range needed for your area, as some plants are much hardier than others. Our range should not be compared to the R. indica types which are sold as houseplants and are not fully hardy outside. Evergreen azaleas prefer light dappled shade, though they will tolerate sun or shady positions.

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 3 plants per m². 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. Evergreen azaleas are suitable for growing in pots and containers; re-pot every 3 years for best performance.

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

Our website calculates the delivery charge according to weight and delivery location throughout the UK. To see these charges, please enter your postcode at the checkout, and you will see the charge vary as you add more items to your wheelbarrow.

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