I own a lot of outdoor containers that can withstand the winter months. Instead of hauling them in and out of my garage to keep plants from dieing, I experimented with perennials these past years to see if any survive, regardless of my efforts.
I have found several plants "keep on keeping on", in my containers when spring arrives.
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| Here is Lamium maculatum "pink pearls". Dead Nettle is the common name. I use it in the corners as a trailer to spill over the container. Quite drought tolerant and has great frost tolerance too. |
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| Here it is again. There are many cultivars are on the market with silver foliage, white, pink, pale purple flowers. Some golden foliage, some variegated. Plenty to choose from. |
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| This is called: Lysimachia nummularia 'aurea' or Golden Creeping Jenny. In this cast iron urn, both plants have come back for over 4 years. I just replace some of the soil at the top of the container, and top dress with a slow release fertilizer. I water more regularly, simply because of it's small diameter. |
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| This plant in the centre is also a member of the Lamium family. This one is however rather aggressive in the garden, used often as a fast covering ground cover. It's called Jade Frost Lamiastrum (Lamiastrum galeobdolon 'Jade Frost'). Here I planted it with an obelisque. As the plant tendrils reach out, I gather and weave the stems throughout the obelisque. It really works well as a vine. Yellow flowers begin in late April, early May and then larger variegated foliage continue to grow through til frost. |
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| This hosta looks as though it's planted in the garden. |
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| Nope! This hosta fills a spot easily and can be moved to change the garden design when necessary. One great aspect of hostas in containers: less watering than annuals. This is a great choice for those cottage dwellers on weekends. ;) |
One key element that needs to be mentioned is drainage. All these pots have good drainage. This is essential. Any perennial that stays soggy and freezes in total water may not survive in a pot. Be sure to notice that the containers drain thoroughly. If you're worried that soil will wash out from the drainage holes, stick a pine-cone or large gravelly stones over the hole. This way water drains, without soil.
With hostas, it's better to group the pots together, insulating them a bit if placed in an exposed area. Sometimes hostas require no garage placement, sometimes they do. If the hostas have outgrown their pots (root bound) some dieback is noticeable overwinter. If you leave them outside in pots, group and situation in an area with just enough protection from the prevailing winds.
What perennials have survived overwinter in your containers?
