Fertilizing Limelight Hydrangea Tree

(Question)

Should I fertilize my limelight tree and what time of the year. I live in Orangeville northwest of Toronto. I realize it should not be done this late in the year.
Thanking you in advance

(Answer)

Thank you for contacting the Toronto Master Gardeners regarding your standard Limelight Hydrangea.

As the long hot days of August continue and most flowering plants peter out from their summer performance, one plant that is center stage is  ‘Limelight’ hydrangea. The conical-shaped flowers have a lovely lime-green tinge when young, maturing to white during July and then occasionally develop a pink tinge by August as the night time temperatures begin to drop.

Hydrangeas appreciate organically rich, well-drained soil. Unlike the mophead and lacecap hydrangeas that bloom on old wood from buds formed the previous year, paniculata type hydrangeas bloom on new growth. For that reason, they should be pruned in the spring before new growth emerges in order to avoid cutting off the buds. Because “Limelight” blooms on new wood, pruning in spring to shape the plant won’t diminish its flower display.

You are correct in your assumption that August it is too late to fertilize your hydrangea standard. Fall is the time for hydrangeas to begin preparing for dormancy. Fertilizing at this time may stimulate new growth that will be too tender to withstand the winter.

Feed “Limelight” twice yearly in April and June with 10-10-10, general-purpose fertilizer. After applying the fertilizer at the manufacturer’s specified rate, then water the plant so the fertilizer penetrates the soil. A yearly application of of organic material such as compost around the roots, produces excellent results and also improves the condition of the soil. Organic additions to the soil can also be combined with a shot of chemical fertilizer for maximum effect.

Here’s to continues enjoyment of this beautiful shrub.