Hydrangeas
- Dramatic summer shrubs
- New, long-flowering varieties
- Superb for fresh and dried arrangements
- Colorful native species
- For borders and containers
Local Advice for Local Gardeners
With an unexpectedly wide range of varieties, hydrangeas are among our most popular and varied Summer flowering deciduous shrubs. The added bonus in many is bold, attractive foliage, which may develop golden or rusty antique Fall colors. Whether you love huge mophead flowers, the more doily-like lacecaps, the later-blooming big PeeGee or the native Oakleaf and Smooth hydrangeas, there’s space for them in all gardens, especially since they can all be kept to a modest size by simple pruning.
The hydrangeas.......
- Bigleaf/Mophead hydrangea (H. macrophylla)
- Bigleaf/Lacecap hydrangea (H. macrophylla)
- Panicle hydrangea (H. paniculata), such as PeeGee
- Oakleaf hydrangea (H. quercifolia)
- Smooth hydrangea (H. arborescens)
- Serrated hydrangea (H. serrata)
- And more........
Hydrangeas like:
- Soil - Happy in most soils: acid or alkaline is suitable, but improve the soil with organic matter when planting
- Light - Thrive in sun or partial shade; most like protection from hot afternoon sun
- Moisture - Hydrangeas enjoy plenty of moisture but do not like being waterlogged; Bigleafs and Smooths will need the most moisture.
Blue or pink?
The color of the flowers on many Bigleaf hydrangeas (except white-flowered varieties) changes with the soil; blue on acid soils, pink on alkaline (limey) soils. You can usually get blue flowers on alkaline soil by applying Aluminium sulfate fertilizer in Spring. If you want them pink on acid soil, add lime each year in Spring. Changing the color is fastest and easiest in containers.
Where to grow plants
- Shade gardens - Many thrive in partial shade; Smooth hydrangea will even take shade all day
- Native plantings - Smooth hydrangea is a valuable Pennsylvania native shrub especially beautiful in woodland gardens
- Containers - Many, especially the repeat flowering types, are ideal in large containers
- Informal hedges - Bigleaf and Serrated hydrangeas make colorful low hedges
- Borders - All are excellent in mixed and shrub borders, either formal or more casually styled
- Specimens - Panicle hydrangea in particular makes a dramatic specimen and an eye-catching focal point, especially if pruned lightly in early spring
Cutting and drying
Cut Bigleafs as fresh cut flowers in Summer when the flowers are completely open, or shortly before. For drying, cut them not in mid-Summer while they are at their most colorful but in late-Summer and Fall when they take on an antique look; place stems in water out of sun and let water evaporate as flowers dry naturally.
Seasonal care
- Spring - Planting time, preferably mid or late Spring. Prune Panicles and Smooths hard as growth starts unless a large specimen is required. Snip back dead shoot tips of Bigleaf and Serrated to just above a swelling bud. Mulch well. Apply lime or fertilizer as colorant, if desired.
- Summer - Plant now if you can be sure to keep your plant watered. Feed with a balanced slow release fertilizer. Prune Oakleaf and Bigleaf hydrangeas after flowering to control height; prune Smooths after June bloom for a repeat flowering in fall
- Fall - Planting time. Cut Bigleafs for drying.
Terrains Top Ten Hydrangeas
- H. arborescens ‘Annabelle’*
- H. macrophylla ‘Blue Billow’* (lacecap)
- H. paniculata 'Limelight'*
- H. quercifolia ‘Snow Queen’*
- H. serrata ‘Preziosa’
- Endless Summer® Series (mophead)
- ‘White Dome’
- ‘Pink Diamond’
- ‘White Moth’
- ‘Tardiva’
Pennsylvania Horticultural Society Gold Medal Plants (www.goldmedalplants.org)
Did you know there is even a climbing hydrangea, Hydrangea anomala subsp. petiolaris, which climbs tree trunks by clinging like ivy?
Written by Graham Rice