I just bought this hydrangea (pls see photo) at Costco. The temperatures here in Toronto aren’t as warm as a couple of weeks ago and I’m wondering when I can put it outdoors on my porch. The tag says Hydrangea Horentsia. I’m also wondering if it would be ok to plant this in my garden later in the spring. I have both sun and shade. Than you :)
Hello fellow gardener
The short answer is you can plant it in the spring and enjoy it but are mostly likely going to be disappointed, long term, as these were never meant to last more than a few weeks indoors. They can be planted and grown but not with the same expectations of a plant that is being grown inside it’s normal season, respecting it’s normal growth cycle.
Long used as a common name for the plant, the name ‘hortensia’ also indicates a specific selection of bigleaf hydrangea, which goes by the scientific name Hydrangea macrophylla ‘Hortensia’. Commonly known as Bigleaf, Garden, French, or Florist hydrangea, is the most economically important member of the Hydrangea genus, with a breeding history spanning hundreds of years.
You could try planting the hydrangea outdoors if weather allows, but it’s important to remember that most indoor/gift hydrangeas were not developed with outdoor performance in mind. A large number of them are not very cold tolerant and will die in winter in areas colder than zone 7 or 8. Obviously, attempting to grow a hydrangea outdoors if you have the space is better than just throwing it away, but if you do plant it in the ground, it’s important to have reasonable expectations about what it will do. For best results, plant it in a protected spot and put down a good 2-3″ layer of mulch over the roots.
Plants grown in Zone 5 should be sited in sheltered locations and given additional winter protection, as needed, for the purposes of minimizing the risk of loss of significant numbers of flower buds or possible die-back to the ground in an extremely harsh winter. A burlap wrap of stems or circle of chicken wire filled with leaves or straw to 8-12″ are time-consuming and visually unattractive landscape options, but can be effective. Regardless of protective measures taken, most bigleaf hydrangeas simply will not bloom (or will bloom poorly) in some years because of a variety of winter occurrences beyond the control of the gardener (e.g. low temperatures, sudden wide temperature fluctuations, icy conditions, late frosts).
For further details and background please look here.
Excellent information is also to be found here.
Another source outlining the hardiness of Hydrangeas (Hydrangea macrophylla) from our website here..