Rhododendron

(Question)

Hello. I planted a small rhododendron in fall 2021. In the spring, it appeared to be alive but unfortunately, I came across it on a hot day lying on its side, with its roots exposed. I think some animal appeared to have dug it up. I trimmed the dead leaves and planted it in a pot, not having a lot of hope it would survive. However, now it has a number of small and healthy looking leaves. My question is about how to deal with it over winter. I can leave it in the pot and bring it inside or I can plant it back in the garden. Is there anything else I can do to give it the best chance at surviving and thriving? I appreciate any advice you can share with me. Many thanks.

(Answer)

Thanks for contacting the Toronto Master Gardeners. Congratulations on helping your newly planted rhododendron to recover from being dug up and left with its roots exposed on a hot day ! It sounds like it is on the road to recovery. I think you have a couple of options at this point as you think about preparing your plant for the upcoming winter.

The preferred option, if you think your plant is healthy and sturdy enough, is to plant it in the garden. It will need enough time to develop roots and get established before the winter, so the sooner you plant it, the better (avoid planting on a hot and sunny day or during a heat wave if you can). You might also want to place some chicken wire around your plant, buried to a depth of 6 inches, braced if needed, and tall enough to keep intruders out, to help to protect it from whatever dug it up when it was originally planted. It would also be good to put a layer of mulch (3-4”) around but not touching your plant. Later in the fall, you can prepare it for winter, with lots of watering, more mulch if needed, and by building a windbreak, using wooden stakes driven into the ground, or bamboo stakes forced into the ground and tied together at the top to form a teepee-like structure. When a hard freeze is expected, wrap burlap around the stakes or teepee, then secure the burlap with twine. This will protect your plant’s leaves from cold, drying winds during the winter.

Your other option is to leave your plant in its pot. Good drainage is essential, since while rhododendrons like moist soil, they do not like wet feet, which will most likely lead to root rot. In the late fall, bury the pot in your garden, which will insulate the roots during the winter. Put a good layer of mulch (3-4”) around but not touching the plant, and build a windbreak as described above. If your plant looks like it is fragile and still struggling, you might want to consider this approach for the winter, and then plant it in your garden when the soil warms up in the spring.

I do not suggest bringing your plant indoors for the winter. I think it is probably still in a weakened state, and the low light, warm temperature and dry air will make it very difficult for your plant to thrive or maybe even survive.

Detailed information about rhododendron care including watering (rhododendrons have fibrous roots, not tap roots, so it is critical to get this right, especially for young plants), transplanting and winter protection can be found at the American Rhododendron Society website here.

Landscape Ontario also has a good article on winter protection here.

Good luck with your rhododendron !

Aug 16, 2022