Why You Should Know Your Zone (and Know When to Ignore It)

Know Your Zone

Every gardener should know the zone in which she gardens.

I write that out with confidence now, but I admit that I gardened for a decade in Chicago without knowing my zone, and I gardened for two years in Florida, where I knew my zone but didn’t know why it mattered.

Pictured above is an image for U.S. gardeners (who can find their zone right here), but Canadian and European gardeners have zones as well. Begin with a google search and then confirm by asking a gardener in your area.

The lower the zone number, the colder your winter temperatures.

Use Your Knowledge

Your zone is your first guide for which plants will be “hardy” in your garden. In other words, your zone tells you–with reasonable accuracy–which plants will still be there in your garden after a typical winter for your area.

When I am shopping for roses, in particular, I look for information about their hardiness. If research or a plant label tells me that a rose is only hardy to zone 7 or 8, I won’t bring it home to my  zone 6 garden.

If I find an inexpensive flower or vine that isn’t hardy in my zone, I may grow it as an annual, tossing it onto the compost heap when cold weather comes.

If I’m interested in a plant, and the label says its hardy to zone 4, then I know that this plant can handle bitter winters, and I won’t bother with extra winter protection.

Set Your Knowledge Aside

Fortunately, there are no garden zone police! And you are welcome–invited, even–to experiment with plants outside your hardiness zone.

For instance, if I really want to grow a camellia that is only hardy to zone 7, I will choose a very protected spot, and I will research the details of camellia care. If I can give that camellia ideal conditions and a little additional care, there’s a good chance it will thrive.

A Few Additional Thoughts

Growing zones aren’t a perfect guide, and they work more effectively in some areas than in others.

For instance, the growing zones are based on temperature, not precipitation. An insulating layer of snow can protect plants from extreme cold, and frequent freeze/thaw cycles, of the kind I often have in my Pennsylvania garden, can devastate certain plants that should be hardy.

Summer heat, humidity, precipitation levels: all these must also be taken into account, but a garden’s growing zone is a good place to begin the privileged task of knowing your own place well.

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Soil is Everything


Death, with all its loss and grief, creates the soil, the womb for life to seed, to take root, to thrive and flourish. Each day, my family and I live because something once alive transfers its energy into our own bodies. And someday, our own bodies will break back down into the dust, providing for whatever life comes after us. On this carefully, lovingly fashioned earth, death and life are not two separate beings but are instead two sides of the same coin. – Catherine McNiel, All Shall Be Well

Soil is the most vital component of our gardens. Everything depends on it.

As gardeners, we would do well to consider ourselves caretakers of the soil. Taking care of the plants themselves is a distant second, because–given the right, healthy soil–most plants can take care of themselves.

How can we take good care of the soil we have been given? Here is one way:

Do Less

It is one of those ironies of the garden, but often we can do better by doing less.

  • Dig and till less: tilling, especially, is sometimes necessary when breaking new ground quickly, but it can also cause the soil to compress and can disrupt the natural, healthy life of the soil
  • Use fewer chemicals and salts: too many chemical fertilizers give a short-term illusion of abundance, but once that season’s annual flowers have bloomed their hearts out, our soil is left depleted and–sometimes–even poisoned
  • Remove less natural vegetation: don’t discard fallen leaves: chop them and use them as mulch; don’t yank out dead annuals: cut off their tops and leave the roots to decompose underneath the ground


How To Keep Containers Looking Their Best


The most important way we tend our container gardens is through feeding.

Plants set out in a garden can usually get the nutrients they need from the ground, but plants in a container quickly use up the nutrients available to them in that confined space.

Some gardeners use potting soil with slow-release fertilizers included, but I prefer not to use these. I like beginning with a basic potting soil that includes no chemical fertilizers. One reason for my preference is that at the end of the season I like to add the spent potting soil to my compost heap, and I really do not want to add chemicals or salts to anything I’ll use in other areas of my garden. As well, those fertilizers don’t feed forever. So, a few months in, some sort of feeding is still necessary.

As an organic gardener trying to tend my soil as much as my plants, I feed my containers weekly through the growing season with a liquid fish or seaweed emulsion.

It is very stinky stuff, but application is easy. I add a spoonful to a watering can, fill with water, then give each pot a good soaking.

Organic liquid fertilizers are:

  • easily absorbed by roots and leaves
  • less likely than granular fertilizers to burn our tender plants
  • and they don’t leave behind harmful residue in the soil.

The hardest part might be remembering to use them.

I remind myself with the phrase “Friday Feed.”

If it’s a Friday, I feed. If I can’t remember when I last fed my container plants, I simply wait for the next Friday and get to work.

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How to Grow Bulbs in Containers


I love to grow spring-blooming bulbs like daffodils and tulips in pots.

Not only is it easy to do (you pot up the bulbs in fall when you would normally plant them in the ground), but when spring comes, you have the option to move your pots around wherever you’d like a splash of spring color.

Two things to keep in mind:

  • Most tulip varieties do not return well the following year. After my tulips finish blooming, I add the bulbs to my compost heap and use the container for a new arrangement.
  • Daffodils are much more reliable perennials (and unappetizing to deer and other animals!). After my potted daffodils finish blooming, I pull out the whole clump and replant it somewhere sunny in my garden. The green daffodil leaves will continue feeding the bulbs, and I’ll have daffodils in that spot next year.

Bulbs in pots can be planted more shallowly and closer together than when we plant them in our yards.

Here is my process:

  • Using clean pots and freely-draining potting soil (I sometimes make my own by adding vermiculite to a heavier purchased potting soil), place a single layer of bulbs in your container, a few inches below the surface, depending on the size of the bulb. Bigger bulbs can be planted a little more deeply. Plant them very closely but not touching. Leave enough space to cover with soil up to an inch or so below the surface of your pot. If you fill your pot to the top, you will lose soil every time you water. I also like to cover my soil with fine gravel or pebbles. Then, when I water in spring, the soil doesn’t splash up and dirty my flowers.
  • Label and water very well.
  • Place in a dry, protected place that will stay cold but not too cold over the winter. Bulbs need winter cold in order to bloom, but when they are planted in the ground, soil insulates them from the worst temperature extremes. A cold garage is a good place to keep them until they begin to push up green growth in the spring.
  • Don’t water again until growth begins in spring. Gradually introduce your containers to the bright outdoor light in spring.

I recommend ordering bulbs in the spring when it’s easy to look around and see what you’d like to grow. Your mail-order company (I like Brent and Becky’s Bulbs in Virginia) will then mail you your bulbs at the right time for planting in the fall.

How to Prune a Lilac (and a book recommendation)


I’d never had a lilac of my own until we moved to Maplehurst in Pennsylvania. They don’t grow in the deep south where I grew up.

I didn’t even recognize the lilac for what it was–I’m embarrassed to admit this–for several years. The reason is that our old lilac shrub hardly bloomed at all, and the blooms it did have were high and hidden.

My lilac was in desperate need of rejuvenation through a good and thorough pruning.

I realized this only after bringing home a wonderful  book: Lee Reich’s The Pruning Book.

I bought that book because I needed to learn how to prune our fruit trees, but the book rescued my lilac.

Two things to consider:

  1. Some old lilacs have been pruned into beautiful tree shapes. DO NOT cut back those thick, beautiful trunks. Instead, rejuvenate in a way that adds to their beauty: cutting out dead or diseased wood, cutting back any suckers to the ground, trimming back any over-long, drooping limbs, cutting out some of the thin, wispy growth in order to introduce more air and light into the center of the lilac.
  2. If your old lilac is a twiggy, shrubby mess like mine was you can drastically cut it back (an easy approach but the lilac won’t look good again for a few years) or gradually prune (a little more time consuming but maintains the appeal of the shrub from year to year).

I chose to gradually rejuvenate my lilac, but even the very next spring I had far more beautiful flowers. Here is what I did:

  1. First, I removed big, old stems that were pointing in directions I didn’t like. I cut them back right at the ground.
  2. Second, I cut out some old stems from the crowded middle of the shrub, again, cutting back down to the ground.
  3. Then, I thinned out some of the younger stems so the shrub wasn’t too crowded overall.
  4. Finally, I cut back some stems that were too long and drooping. I didn’t cut them to the ground, just trimmed them back a bit.

For on-going maintenance, the best time to prune a lilac is just after the blooms fade.


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