Paging through an English garden magazine recently, I saw a column devoted to the snowdrop chapter of the unwritten garden rule book. Traditional wisdom holds that snowdrops should only be divided and transplanted “in the green”—just as the blooms fade in early spring. Many snowdrop growers have followed that rule since the beginning of time—or at least the beginning of cultivated snowdrops—and it is very successful. It makes sense too. Snowdrops are spring ephemerals, meaning that all traces of them disappear within four to six weeks of the time they finish blooming. When snowdrops are “in the green,” they are visible, which makes it a lot easier to lift the clumps of tiny bulbs and separate them.
The author of the column argued that rules don’t have to be hard and fast. In fact snowdrops can be lifted and divided any time except when the ground is frozen. If you can find the clump and dig around it without injuring the bulbs; you can divide it. This is helpful, especially if you, like many of us, generally have too much to do in the garden, not to mention outside its boundaries. The key is common sense. If you think you will want to divide your snowdrops after their annual vanishing act, mark their location with small stakes or take a picture of the spot, including enough nearby identifiers so you can find it accurately. By taking that quick step, you have given yourself the freedom to divide with impunity and your snowdrops will be none the worse for it.
The snowdrop column made me think about other garden rules and the wisdom of breaking them on occasion. I came up with several.
Zone Hardiness: The United States Department of Agriculture publishes the “Plant Hardiness Zone Map,” a helpful guide that shows the average annual minimum temperature for all regions of the United States. The lower the zone number, the colder the area. Plant breeders and vendors use the zone numbers to provide guidelines to wholesale growers and retail customers. It is a great tool. However, every region and every garden has microclimates. If you happen to have a protected spot or spots where the snow melts first and weeds appear in spring before they pop up in other parts of the garden, you might be able to support a plant that is not technically hardy in your zone. For example, if you live in USDA Zone 6, your sunny protected spot might be able to support something listed as only being hardy to Zone 7. Don’t be intimidated by numbers. Try that plant—provided it doesn’t cost a million dollars–mulch it well and give it supplemental water during dry spells. Protect it during the first winter. You will probably be surprised at its hardiness.
Pruning: There are so many unwritten, set-in-cement shrub pruning rules that many people are afraid to prune at all. This is why you see rhododendrons the size of wooly mammoths, octopus-like forsythia and hollies threatening to subsume entire houses. If bushes flower, refrain from pruning them until the flowers fade. Prune by one third under normal conditions, one half if things are slightly out of hand and two thirds if the shrub is already eating pets, small children and large garden tools. Sharp tools work better than dull ones. You can prune any time the urge strikes you, except before flowering shrubs flower. You can prune at that time as well, you will just miss a year of blossoms. Try to give the shrub a pleasing shape, but if you make mistakes remember that even radical pruning will not kill a healthy shrub.
Mid-Summer: Garden pundits always tell you to avoid doing most things—planting, transplanting, pruning—in mid-summer because the high heat and absence of moisture will stress the plants. The pundits are right, but if mid-summer is the only time available to do those chores, carry on. You will simply have to give lots of water to new plants and transplants and mulch them thoroughly. If a new plant is showing signs of stress from Sahara-like sunshine, arrange some shade for it. Pruning is hard for human beings in summer, but plants, if carefully tended, will take it in stride. Drip irrigation helps almost all plants, including transplants and the newly pruned, get through the heat. Soaker hoses are inexpensive, hook up to your garden hose and can be put on timers so that your plants will be cool and comfortable while you are toiling away in the occupational salt mines.
When I first set up house on my own, I was convinced that God would strike me dead if I didn’t dust the baseboards once a week. Clearly that was not true, because I am still alive. Having broken a good many domestic and gardening rules in my time, I can say with authority that you will not be struck by lightening if you transplant your snowdrops in August. Respect the rules, but don’t be afraid to embrace the exceptions.