Experts agree that, with a little TLC, hydrangeas can grow here on the Space Coast

For many, the pompom blooms of hydrangeas evoke memories of their childhood.  The old-fashioned “snowball” variety from grandma’s yard has undergone a makeover with an abundance of new varieties. Among those reported to do well in Florida (Zone 9) are Nikko Blue, Domotois and Brestenberg and the native Oakleaf Hydrangea. Gardeners and landscapers have renewed interest in hydrangea because it flowers in shade, often produces blue flowers, and is considered an “heirloom” plant that reminds us of the garden heritage of our forefathers.

Planting

Apply lots of compost to the soil when preparing the planting hole if you have sandy soil.  Hydrangeas are traditionally known as shade garden plants, but too much shade can result in reduced bloom production. Ideally they should be situated in areas of light shade to partial sun

Plant where they get morning sun only. Shade is needed starting around 10-11 a.m. or the leaves will sunscorch.

Locally grown hydrangeas will still go dormant but very late, around January or so. Then they will leaf out about a month later. A reblooming variety like Endless Summer takes advantage of our long growing season.

If the ground never freezes in your garden, plant hydrangeas in the fall and winter.

They also need good air circulation to prevent mildew.

Watering

Hydrangeas require a lot of water, about fifty percent more than normal because of our sandy soil.  Due to the heat (like other non-tropical flowers in this climate), bloom colors are a bit washed out when summer heats up.

Water deeply and slowly twice a week. A soaker hose works well for this. The soil should be completely saturated at each irrigation and allowed to dry to within 1 inch of the surface prior to watering again. If the leaves wilt or droop, water the plant.

Fertilizing

Add a controlled-release, balanced (10-30-10) fertilizer to the soil in June and August for a bloom boost.  Remember that too much nitrogen will result in an abundance of leaves at the expense of blooms.

Hydrangeas come in an array of colors including pure white, chartreuse green, blues, purples and pinks. A mophead hydrangea turns blue only if there’s aluminum present, found naturally in acidic soils. If your soil is alkaline, add aluminum sulfate to turn blooms blue or just enjoy the pink color.  Not all hydrangea varieties react similarly to soil changes, but you can experiment with color by adding lime to the soil.

Pruning

Since new stems grow throughout the summer, keep spent flowers clipped to promote new flowers.

Little pruning is required with old-fashioned hydrangeas. In fact, improperly pruned bushes can result in bushes not producing any blooms.

If you need to prune to keep it to a desired shape or size, do so in the spring.

The most common reason why hydrangeas don’t bloom is improper pruning.  Most hydrangeas bloom on old growth or last year’s wood.   If you cut too much of that old wood off when you prune or you cut that wood too late, you won’t get blooms. 

Remonant (reflower on new growth) varieties

Cultivars that are free flowering (reflower from old growth)

New and notable cultivars.  Most do not normally reflower in the same growing season

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