It is prettier than the old map, interactive (click on it to check out the zip code zone finder), and the information is finally up to date. But it’s not good news and there are no surprises here. Nothing we haven’t already figured out for ourselves. The new map is based on weather-station data collected between 1976 and 2005 (as opposed to the 1990 map, which was based on data from 1974-1986.) I’m actually surprised at the similar spread of years used in the data collection – it feels like the temperature changes have been more wildly noticeable in the years since the last map was drawn and with that bias the map might tell a different story. We are living through proof that wild swings occur from one year to the next and so far this wimpy winter could count to notch our zone even higher.

Blithewold is solidly within the very cusp of zone 7a. (My garden a mile and a half away is 6b.) But we have always called it zone 6 to play it safe. That way we can be pleasantly surprised when marginally hardy plants come back to life again in the summer. Aucuba japonica (zone 6-10) has always bounced back for us – I only remember one winter that almost did it in. Harlequin glory bower (Clerodendrum trichotomum, zone 7-10) has been perfectly hardy too, not even dying back to the ground like the books say it should when it lives on the edge. Ours has had the protection of the North Garden wall (seen in the picture below recently repaired.) Salvia guaranitica (zone 7-10) has come back for us in the Display Garden herb bed for the last 3 years or so.

I’m tempted to use this map’s confirmation of what our experience has been to finally call our zone a 7, and as an excuse to make the best of it and test the hardiness of a few more plants. At home I have successfully overwintered leopard plant (Farfugium japonicum ‘Aureomaculata’, zone 7-8) and am trying cast iron plant (Aspidistra eliator, zone 7-11) and Tetrapanax paperifer (zone 7-10) this year. Perhaps if we found just the right spot along a south facing wall, (I have such a spot at home…) a winter blooming Edgeworthia chrysantha (zone 8-10) could be coerced to return. But I suppose that would really be pushing it. (So to speak.)

Of course it bears remembering that zone hardiness isn’t the only measure of a plant’s ability to survive in our gardens – soil quality, light and moisture levels are at least as important, over winter and summer. Has your zone changed? Will you use the new information to take a chance on anything new?

Don’t tell anyone but I am not a big fan of potted mums. For weeks now they’ve been popping up on doorsteps everywhere and plopped pot-and-all into every other foundation bed, and I can’t help yawning. They’re just so… municipal. Now, you know me – I’m all for whatever gets people buying plants and out in their gardens/yards, but mums? Really? There are so many other things that are more interesting – including …  mums.

Hardy Chrysanthemum – or Dendranthema or whatever the kids are calling them these days – are so much lovelier than the ones that are forced into bloom only to die from neglect or stress a few weeks later. Hardy mums have a looser more graceful form – extra loose if we forget to cut them back in June – and they live for practically ever and tend to be generous spreaders. Sheffield Pink is our grandmotherly favorite, spread along the edge under the dawn redwood hedge in the Display Garden and borrowed with something blue in the Rose Garden. I don’t know and haven’t been able to find the name of the sweet yellow and red one in the Rock Garden. Anyone recognize it?

It should be noted that some of the potted mums for sale are hardy mums in disguise. Neither Gail nor I remember planting the deep-pink mum in the North Garden and have credited a wedding decorator. (We toast the happy couple every fall.) Over the last few sunny days, it has been as covered with different species of bees, flies, wasps, etc as any aster. And that right there is reason enough to plant the hardy mums – they’re a great late meal for pollinators.

Potted mums have become part of people’s -non gardeners and gardeners alike – fall tradition but wouldn’t it be great if growers started forcing Cuphea micropetala instead? Aside from being an outstanding tender perennial worthy of a position in the garden from June on, the late summer-into-fall flowers look just like candy corn. And I know at least one nursery owner who puts luminous Plectranthus ciliata on display in the fall. I’m sold. How about you? Do you buy potted mums or have you made another late-fall flower part of your garden’s tradition?

On the one hand, I can hardly help but want to group plants together and if there’s a pot big enough for everyone, I’m all for it. And there are places in our gardens that truly demand a mixed container, such as the entrance gate, wedding tent, and porte-cochère. I spent the last two weeks debating buying what seemed to be a behemoth new container (made of very light-weight and hopefully winter-durable resin) for our entrance. I knew the one we were using was way too small but it took Gail’s reassurance and actually seeing the new pot situated to realize that there’s almost no such thing as “too big” for a solitary container placed outside.

I’ve been pretty lucky with these mixed containers in the last few years (last year in particular) but I attribute their success (and by success I mean that they don’t need to be watered more than twice a week) to one very important factor: They’re in partial shade – receiving only morning sun. Glazed or plastic pots obviously hold the moisture longer and I think relying heavily on perennials (or tender perennials) with interesting foliage rather than flowers has helped too. Most of my favorite container plants – such as hakonechloa, farfugium, hypericum, Geranium ‘Rozanne’, and hydrangea will also grow slowly enough in confinement to not overtake their neighbors.

But for the container beds by the greenhouse I would much rather group singletons in pots than plant up a bunch of mixed combinations – for a couple of reasons: One of the beds is in full sun, and in my experience, mixed pots in full sun are a constant struggle. There’s more competition for soil moisture and inevitably something dies and leaves a gaping hole or one thing overtakes and might as well have been planted by itself. (Obviously I haven’t hit the exactly right full-sun combo yet.) With singletons on the other hand, wimps can be babied and tucked behind athletes at least until they’re tough enough to compete. The whole bed can be rearranged on a whim, and as a nester and obsessive futzer, I’m all for that. The only difficulty is pairing pot to plant. But even that is a challenge I look forward to every year. And I have to admit that I never really mind if something like fleabane (Erigeron karvinskianus) or violets seed themselves in, and so most of our singletons are actually couples.

Do you prefer mixed containers or singletons – or do you have places for both too?