Rhododendron Yellow Hammer AGM

Superb small tubular bright yellow flowers in April, (and often again in the early autumn). It has a narrow upright habit which does benefit from pruning to maintain shape. Best in light shade and it does need good drainage. It makes a super cut flower. Height 80-100cm in 10 years.

• Recommended for super bright yellow flowers.
• Easy to grow.
• Ideal position: needs careful site selection.
• Habit: Upright.
• Group: Rhododendron hybrid.
• Parentage: sulfureum (s) X flavidum.
• Hybridization date: pre 1950 (before 1931).
• Bred by: J.C. Williams. Origin: British.
• Ideal soil: pH 4.5 to 6.0
• RHS Hardiness Rating: H5.
• How we usually propagate this plant: Cutting.
• Awards: RHS Award of Garden Merit.

Good to know

Small Leaved Rhododendrons such as the cinnabarina and triflora sections will grow 75-150 cm in 10 years often with an upright habit. Their smaller leaves, which can be glaucous, contrast with dense tall hybrids, and really softens the landscape view and creates added interest.

Those in the cinnabarina section often have stunning brightly coloured waxy tubular bell shaped flowers.  They can suffer from powdery mildew, but we have selected a modern range which are resistant, provided they are planted where air circulates freely.

The triflora section are also full of character, with more open flowers, in shades of pink, white and mauve.

Rhododendrons like moist acidic soil, with good drainage, and plenty of organic matter such as leaf-mould and added ericaceous compost. They should be given the best planting positions, which are neither too wet nor too dry. 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 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. Best grown in dappled shade or sunny positions with in a slightly breezy position to allow good air movement. Some varieties can be damaged by deer.

Please note: Due to their upright habit, some varieties can look a bit sparse and thin in a pot, but will soon fill out once planted out. Not recommended for growing in pots, as they can look a bit sparse, and their habit can make them top-heavy..


For further advice, For further advice, see here

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

Size Guide

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.

Please see here for delivery information

Please see here for cancellation and return information