How do I winter-over flowers?

Question

I have 7 window-boxes filled with perinneals. Lavender, lemon-balm, spearmint, aztec pearl verbena, toto black-eyed susan, and veronica. I know these are all flowers that spread and get "shrubby". I have two flowers planted in each 2-foot planter. I need to know how to winter them over. Do I simply cover them? Can I plant them in seperate buckets and put them in the basement? I want them to come back next year, but I have never planted perinneals in planters before. Help!

Answer 1

I don't know where you live... I am in Minnesota and because it gets so cold, we cover everything with layers of leaves and sometimes tarps.

I would recommend taking all your planters and placing them 'together' and then cover them well, with mulch or leaves, once fall comes... keeping them from drying out and freezing out in the winter.

some perennials can be brought inside if you want to prolong the 'wintering' ... I have done geraniums this way before.... otherwise, I just bury plants under leaves and snow for the winter and they do fine!

Answer 2

What zone are you in?

Overwintering perennials is best done with the container in contact with the soil. So you will either need to remove the plants and place in pots for the winter or move the window boxes down to ground level. Once freezing weather arrives, place the pots and/or planters on the ground and cover with leaves or straw. This will prevent alternate freeze/thaw cycles during the winter.

In the spring uncover the plants and replace the boxes or replant into the boxes. Removing the plants will be necessary either in spring or fall anyway so that you can divide them. They will grow too big for the window box without annual dividing.

Answer 3

Unless you have a ground to put them in then over-wintering them will be next to impossible. These are full sun plants. Indoors and they won't get enough light and staying in the boxes won't protect their roots well enough especially if you live in a particularly cold zone. Plants with roots need to be in the ground over winter. Bulbs or Rhizomes can be pulled up and stored in a dry dark place for winter. So, for the lavender and black-eyed Susan then I would say no, but maybe to the lemon balm and spearmint because these two are like weeds. Keep them watered and put them in a bright window and they may make it, however, they will probably be a bit leggy.
One other thing you could try is to set up a grow station in your basement (provided it is warm enough) with bright grow lights and try to over-winter them that way. You can purchase Fluorescent fixtures and place one warm bulb and one cool bulb inside the fixture. Put your plants directly under the fluorescent fixture with about 3-4 inches of space from the fixture to the top of the tallest plant. I'm sorry, wish I could be more help. Good luck