At this time of year my garage is packed to the rafters. Sure, I have the usual assortment of snow shovels, ladders, fertilizers and other garden products. There is a rack of boots, some brooms and the garbage cans…normal garage stuff. But from December through April, my garage is also packed with plants.
There are some plants that may not survive in containers outdoors, yet they don’t need to be in the house either. Some, like the fig trees (somehow we ended up with three large pots of Brown Turkey figs), lose their leaves and are dormant. Others, like the huge bay, are semi-dormant and do well enough by a small, eastern-facing window. Then there are the potted Hydrangea and Agapanthus: these are placed wherever there is a space, allowing that the cars do need to be able to pull in before a snowstorm.
In short, the plants are more stored in the garage than they are grown here.
And they do just fine. The key to success with garage storage is that this area is attached to the house but not heated. The garage never goes below 32 degrees but tends to hover in the 40’s and low 50’s all winter. This keeps the plant dormant but the plants never freeze.
Watering is needed, but not too much or too often. I’ve found that if these plants are watered every three to four weeks, depending on the temperatures and the size of the container, that this is perfect for keeping the roots from drying up. Too much water is likely to rot the roots, however. When plants are dormant they are not absorbing much water, so if the pots sit in saucers that are filled with the overflow this can lead to root rot. Yesterday I had to use a broom to sweep excess water onto the garage floor and then out the door, since these pots are too large to easily move them out of the saucers so that they could be emptied.
Other than watering, the only tricky part of garage plant storage is what happens in February and March. As the days lengthen the plants start to break dormancy, even though there really isn’t enough light to sustain this growth. If the weather is fairy mild I can pull varieties such as roses and hydrangea outside to slow them down. But if it’s too cold they must remain in semi-darkness until the weather improves. At that point I need to gradually reintroduce them to the real world so that the leaves don’t get sunburned. I do this by grouping them near the garage door and opening it for short periods so that the sun can come in. I might do this for only fifteen minutes in late-March and moving to longer periods in April. Finally, once the weather is mild enough, but hopefully on a cloudy day, I move the plants outside for the season.