Happy Hydrangeas

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Hydrangea paniculata Phantom

Hydrangea paniculata Phantom

These galleries are almost all hydrangeas with big, cone-shaped flower-heads, (paniculata), rather than rounded mop-heads (though I have included Nymphe in the galleries) – and one oak-leaved hydrangea (with distinctive leaf shape and excellent autumn colour).

They have all been photographed on the slopes of Battleston Hill in the gardens of RHS Wisley, where they are placed close enough to make decent comparisons, one variety over another, but with sufficient space for them to do their thing – for they are shrubs happiest as larger specimens or in a shrub border. Glorious green tints and flushes of pink develop as many varieties mature (others remain pure white or cream) and the significant flower-heads can be left, gently decaying, on the plant until pruning is needed in late winter/early spring the following year. With low, late sun and a touch of frost, they can look bewitching.

Once again I turn to the sainted Val Bourne for further insight…

Hydrangea paniculata: How to grow

Ursula Buchan gives her advice on growing this unfussy plant – Hydrangea paniculata.
12:01AM BST 06 Jun 2013 The Telegraph
When we think of hydrangeas, it is the mopheads or hortensias that come to mind, since they are such a feature of gardens on acid soil in coastal counties. Admirable as these hydrangeas can be (although too many of them look coarse and washed out), there are a great many others that have as much, if not more, to recommend them.
I am thinking particularly of the dozen or so cultivars of Hydrangea paniculata, the panicle hydrangea, so-called because the flower heads are not rounded but in a broad cone which, botanically, is known as a terminal panicle. These flowers are mainly composed of sterile florets surrounding small fertile ones but, for the sake of simplicity, we tend to call the whole panicle a flower.
Hydrangea paniculata cultivars make medium-size or even large, spreading shrubs and grow at least 3m (10ft) tall and 2.5m (8ft) across at maturity if left unpruned. These shrubs are deciduous, with green, deeply veined leaves 7cm-15cm (3in-6in) long, oval in shape, with a tapering point. The panicles of most cultivars appear in late summer but last into autumn and are at least 20cm (8in) long.
The flowering times vary somewhat depending on the cultivar grown. In ‘Grandiflora’ and ‘Unique’, the panicles are larger than H. paniculata, and white, taking on a pale-pink flush as they age, while the florets of ‘Pink Diamond’ start off creamy-white and age to deep pink with a red reverse. ‘Pink Diamond’s panicles are broad and up to 30cm (12in) long, and always cause comment because their freshness looks so spring-like. ‘Pink Diamond’ should properly be called ‘Interhydia’ but no gardener uses that name.
Other excellent cultivars include ‘Tardiva’, which begins to flower a little later than most cultivars, and the early-flowering ‘Kyushu’, which has loose panicles of creamy-white florets and an upright habit from July on. Promising new cultivars include ‘Limelight’ (pale lime-green flowers) and ‘Burgundy Lace’ (light pink). These shrubs do particularly well in a comparatively warm, wet climate, such as that of the west of Scotland.
Growing tips
These shrubs are not as fussy about soil pH as some hydrangeas, but it must be fertile, well-fed, and slow to dry out. Plant them where they are shaded from the sun for part of the day. Although hardy, they don’t appreciate cold winds, and frost may damage young growth in spring, so plant them somewhere sheltered and neither in a frost pocket nor an east-facing position. Mulching with organic matter in spring will go a long way towards preserving precious moisture in summer.
Pruning
Panicle hydrangeas can be kept compact by pruning. This will also produce larger, if fewer, flowers. Pruning is easy: simply cut back last year’s sideshoots to within 5cm (2in) of the older wood in early spring.
Good companions
These shrubs are happy in a partly shaded position so they associate well with other September part-shade-lovers, such as astilbes and Japanese anemones. Tall Anemone x hybrida cultivars, such as the white ‘Honorine Jobert’ or the pink ‘September Charm’, are particularly suitable. The autumn-flowering Cyclamen hederifolium makes effective groundcover close by. To divert attention from the hydrangea after it has been pruned in spring, you could grow masses of Anemone nemorosa, epimedium, and hellebores around it. Among shrub companions, cultivars of the 1m (3ft) tall Hydrangea serrata (for example ‘Beni-gaku’ or ‘Rosalba’) take on deep-crimson leaf or flower tints, which harmonise well with the white or pink flowers of many Hydrangea paniculata varieties.