The glorious history of Penny Mac hydrangea can be read about other places on Google, but we'll encapsulate it by honoring the namesake, Penny McHenry, for her passion for hydrangeas and gardening. She founded the American Hydrangea Society right here in Georgia.
Penny Mac is a remontant mophead Hydrangea macrophylla from her garden.
This cultivar is a beautiful treasure, a conversation piece, and a garden stalwart. It's a classic "Cape Cod blue" mophead that will stand up to any other remontant mophead, any day and every year.
Penny Mac is considered a pastel-hued mophead, but, as with most macs, the flower color depends on pH and aluminum availability in the soil (low/acid pH = blue and high/alkaline/basic pH = pink).
Some of the pictures show an array of colors on the bushes - that's due to variability of pH in the soil. We love this look, so we shared these pictures with you. The individual flower shots show the blue or pink you typically get on individual plants.
Looking for Endless Summer hydrangea? Penny Mac is the quintessential replacement - her flowers are similar and she reblooms just as well.
A few years ago in a nursery not so far away, a Penny Mac grew a branch with yellow leaves and the "branch sport" (technical term) was clipped off, propagated, studied, deemed lovely, and finally named Golden Penny hydrangea.
Penny Mac bigleaf hydrangea
bigleaf hydrangea, french hydrangea, mophead hydrangea, hydrangea, hortensia
USDA Hardiness Zones
flowering shrub, deciduous
- Spring: medium green
- Summer: medium green
Fall Leaf Color Quality
Soil Moisture Requirements
moist-but-draining, no standing water
Soil pH Requirements
acid, neutral, alkaline
sun, part shade, shade
To Make It Thrive
Give Penny Mac rich soil and consistent moisture in a soil that drains. It may need extra watering, but doesn't like standing water.
Make sure Penny Mac has dappled shade most of the day or at least afternoon shade in the deep south (zones 8 and 9) not only for the foliage, but so the flowers don't get sun scald. Increasing amounts of sunlight is increasingly tolerable the further north one goes on the map.
Traveling northward, consider planting in warm sheltered locations, such as near heated buildings.
Here in zone 8a, we cover to protect flower buds during spring transition - the up and down temps cause flushes of growth that are then zapped by cold. Covering the growth with old terry cloth towels or thermal blankets generally works to ensure summer flowers.
Is 'Penny Mac' remontant?
She sure is, so you'll either get two flushes of flowers in a growing season or, if the first buds were killed, you'll get one flush of flowers in late summer.When do I prune?
Bigleaf hydrangea flowers on old wood, so if you need to prune, do so in the summer after flowering. See our blog posts about pruning