Cultivar or Variety?

In the eighteenth century, when Linnaeus invented the naming system that is still used in biology and botany today, he expected that every plant would have a unique and universally recognized two-word name: the first (genus) capitalized and the second (species) not. Spiraea japonica refers to the same plant the world over.

But sometimes differences arise, as a result of natural mutation or uncontrolled cross-pollination. These differences may be important but not unique enough to justify a new species name. Such plants are called varieties, and their differences are likely (but not guaranteed) to reproduce well from seed. Varietal names, in italics, are not capitalized and simply follow the species name, sometimes set off by “var.” Spiraea japonica albiflora is smaller and paler than its parent.

Cultivars (a contraction of “cultivated” and “variety”) are plants that have been bred or selected for desirable characteristics. They are propagated vegetatively, from cuttings rather than seeds, because their seedlings generally do not reproduce the parent. Cultivar names are capitalized, enclosed in single quotes, and not italicized. Spiraea japonica ‘Goldflame’, with bright yellow leaves and bright pink flowers is considerably more colorful than Spiraea japonica.

All this helps to assure that everyone — no matter what language they speak — can speak the same language when they want to identify a plant.



We’re honored that our blog is regularly followed, and often reposted, by the Strafford County Master Gardeners in Strafford County, New Hampshire. This is a post that appeared on their blog in early January of this year. An interesting idea for our members who also live in a similar weather zone: planting Mache along with our other fall plantings.

The vegetable is clearly growing in popularity as a quick Google search produced over 15 million results, the most recent being on January 24th of this year: Mache — the Sturdiest of Greens for the Winter Garden. Quickly reading some of the Google articles proved to be an interesting study in the different gardening habits around our county and, indeed, the world. Because mache likes cool weather, for those of us who live in cold weather country, it can be planted in the fall to sprout right away in the spring. However (and this is the best part about how gardeners share their experiences), the blog post shared above is from a master gardener who planted in the late summer and was able to harvest it into December.

Hoping someone tries (or has already tried) this and will share their results!



Flowering Branches

ForcingBranches_PinkThis is the time of year when spirits yearn for green sprouts and signs of warmer weather to come. You can hurry nature along with a glorious indoor display of blossoms from the cut branches of spring-flowering shrubs and trees. Forcing branches into bloom is not difficult, and a thoughtful selection of plants will ensure a succession of blooms for several months.

In order to bloom, the plants must have been dormant for 40 to 60 days in temperatures below 40ºF, so choose branches that set their buds in fall or early winter (see below). Look for branches with fat flower buds (the small buds are leaf buds). To preserve the shape and health of the plant, cut branches that you would normally prune.

Scrape about 2 inches of bark from the cut end of the branch and make a 3- to 5-inch slit in the stem end to enhance water absorption. You can also split the end by hammering it gently; be careful to avoid crushing the branch, which would accelerate decay.

Fill a tall container with room-temperature water and place the cut branches in it. Or fillpottery barn image the bathtub and submerge the entire branch — buds and all. Let them soak overnight so that they will absorb as much water as possible. Fill a second container with cool water, add a floral preservative (available from florists), then transfer the branches to a new container. Place the branches in a cool, dimly lit place. In three or four days bring branches into a bright area out of direct sunlight. Change the water and cut 1 inch off the bottom of each stem every week. Mist the branches at least once a day. They may take as long as 3 weeks to bloom, but the sight of all those precious buds bursting with divine color is a glorious reward for your patient anticipation.

Plant List

Blooming times and cutting times will vary according to your location and the weather conditions. The earliest bloomers are witch hazel (Hamamelis mollis), Cornelian cherry (Cornus mas), forsythia (Forsythia spp.), pussy willow (Salix discolor), azalea (Rhododendron spp.), and flowering quince (Chaenomeles).

For later forcing choose from magnolia, apple, and crab apple trees (Malus spp.), beach plum (Prunus maritima), flowering dogwood (Cornus florida), hawthorn (Crataegus spp.), red bud (Cercis canadensis), and mock orange (Philadelphus spp.).

Poisonous Garden

We often hear of people trying to make gardens safe for children and pets. However, there are so many potentially toxic plants that, if you were determined to eliminate every edible hazard, you wouldn’t have much of a garden. In addition to plants like nicotiana and oleander, which are poisonous in every part, there are some plants that have both edible and toxic components, such as tomato and rhubarb. The tomato fruit is safe, as are the red rhubarb stems. But eating the leaves of these plants can cause nausea, convulsions, coma, and in extreme cases, death. Similarly, apricots, peaches, and plums are fine, but their seeds are not, and the bark and leaves of the trees that bear them can be dangerous, too.

Potentially dangerous parts of ornamentals include daffodil bulbs; clematis leaves; the leaves and flowers of mountain laurel, rhododendron, and azalea; leaves and stems of wild black cherry (Prunus serotina); chokecherry (P. virginiana), and pin or wild red cherry (P. pennsylvanica).

Also on the list are English ivy berries; the corms and seeds of autumn crocus (Colchicum autumnale); the stems, flowers, and leaves of monkshood (Aconitum spp.), cardinal flower (Lobelia cardinalis), and Jerusalem cherry (Solanum pseudocapsicum); the leaves and flowers of tansy (Tanacetum vulgare), and truth to tell, several hundred more.

Instead of trying to keep poisons out, we should focus on teaching your children not to put random pickings from the garden — or anywhere else — into their mouths.


And, speaking of poison, did you know that you can get a poison-ivy rash in the winter? Poison ivy (Toxicodendron radicans) is a native North American trailing or climbing vine, and occasionally a shrub. Every portion, including roots and stems, contains an oil called urushiol, which is capable of producing a nasty dermatitis even in winter.

Although in winter the plant is without its distinctive three leaflets, the bare vine can be recognized by the hairy appearance of its brown, leafless stem, which can scale trees to great heights. The numerous dark rootlets and fibers make it look fuzzy.

Urushiol from the stem and rootlets can remain on tree bark even after the vine has been removed, so if you get the rash and can’t remember seeing any likely cause, the problem may be your firewood.

Poison ivy’s garb at other times includes a handsome crimson leaf in fall (often tempting unwary flower-arrangers), tiny green flowers in spring, and white grape-like berries in late summer that may linger through winter. This fruit is a valuable food for birds, which, unaffected by its oil, help spread the plants when the seeds pass through their system.

Victorian Clock Garden


Floral Clock, Queen Victorian Gardens, Melbourne, Australia

Before modern distractions, everyone who lived with flowers recognized that some of them opened or closed at about the same time each day. Linnaeus, the father of modern plant classification, was one of the first to publish a list arranging common flowering plants in an order that could be used as a clock. After all, sundials do not work on cloudy days, and mechanical timepieces were expensive in the eighteenth century.

Floral clocks work in any weather because the photo-sensitive plants that reflect day length actually take their clues from the length of the night, not the day. But no one understood this until much later, and Linnaeus’s list happened to include some day-neutral plants, such as dandelions, which couldn’t care less about punctuality and which change their schedule throughout their blooming season. Most of Linnaeus’s timekeepers are weeds, but his interest was in getting people to work on time, not in having them admire the clock. Whether you want bindweed, thistle, and hawkweed (5, 7, and 8 a.m. in Uppsala, Sweden, where Linnaeus lived) in your garden is up to you.

The summer sun rises earlier and sets later the farther north you are, and flowers open and close earlier, too. Unfortunately for the Victorian-era gardeners who were using his plant lists, Linnaeus lived farther north than all of Britain, the United States, and most of Europe. Consequently, floral clocks rarely produced useful results. Many Victorians ended up including sundials, simply arranging their plants according to whether they opened in the morning or afternoon. Perhaps if Linnaeus had lived in Geneva with the rest of the clockmakers, his list might have been more useful.


Counting Sunny Hours

Cherub584A sundial makes a charming garden accent and, like a birdbath, actually serves a purpose beyond mere ornamentation. But whether it is a common horizontal type (meant to be mounted on a pedestal) or the less common perpendicular form (for wall mounting), a sundial must be placed with care.

  • It seems obvious, but make sure the spot gets unobstructed sun all day.
  • The sundial will be a focal point no matter where you put it, so put it where a focal point makes sense — in the (wide) intersection of two paths, for instance, or at the end of a long axis.
  • The mounting spot must be level, and it must be accessible; if you put the sundial in the middle of a flower bed, nobody will be able to read it.
  • Don’t forget about daylight savings time when you set it up. The sundial should tell the true (sun) time, even though it’s likely to be used mostly in the summer.
  • To avoid mistakes, place the sundial provisionally, without affixing it to the spot, and check it every few hours for a couple of days.
  • Just in case you’re fond of crossword puzzles, the part that casts the shadow is called the gnomon.

Basement Nursery

In an effort to improve seedling production in the spring, you might consider moving your seedlings from a sunny window (that may or may not be sunny every day) to an area where you can install fluorescent lights. Moving seedlings into an environment where the light can be controlled, and the day and night temperatures won’t fluctuate wildly, cries out for a heated basement. Even the sunniest windows rarely offer more than a few hours of really bright light each day, and that doesn’t count the losses because of cloudy days or a light covering of dust or dirt on the window glass.

dbe19db223bbfa992e50b92fe1b12023--a-frame-plant-standsBut even with the fluorescent lights on for 18 hours, seedlings don’t really get enough light. While a fluorescent light looks bright to us, it is a poor substitute to a seedling expecting to bask in the sun. To provide enough light, use two 4-foot-long, two-bulb shop fixtures (available at any hardware store), suspended just 2 to 6 inches above the seedlings.

Special grow lights aren’t magic. Often, there is just a blue coating on the inside of the tube. The overall amount of light is reduced, and the seedlings think they have sunglasses on. A mix of warm white and cool white tubes will give the right kind of light, and more of it.

A small fan is needed nearby to move the air, helping to prevent fungus diseases and to flex those little seedling stems, enabling them to grow stronger and thicker (just like going to the gym). But don’t get carried away trying to make little Arnold Schwarzenpeppers.

Most seedlings like it comfy — temperatures in the 60s and room to grow. If they are too crowded, or if that furnace is overheating them, they will become stretched and spindly. Perhaps they are trying to grow up quickly and get away!

Buy your seeds early while there are lots of choices, but don’t start them too early. Look on each package for the right timing, and mark your calendar.

Earlier posts on seed starting:


Keep Deer-Damaged Hedges


Deer damaged hedge

By now, it is no longer news that deer love classic hedging evergreens such as arborvitae, hemlock, and yew. Gardeners are routinely advised to choose deer-resistant plants instead. But what if you already have the hedge, and deer have already eaten it? What if your newly purchased home grounds are ringed by 20-foot trees that look like lopsided lollipops?

If space is severely limited, you may have to cut them down and start over with something else, but if you have a strip at least 12 feet wide to devote to the area, you can build a better hedge on the bones of what you have.

After all, it’s only the lower regions that need help. Everything above 6 to 8 feet is no doubt fine, and it will only grow lovelier over time. The trick is to go for depth: plant a shorter hedge in front, and you’ll screen the naked area from view while adding textural interest, just as you do when you plant a baptisia in front of rust-prone hollyhocks.

For best results, think in three layers: hurt hedge at the back; good-size shrubs or small trees like holly, lilac, and pieris in the middle; short, full items like mugo pine, boxwood, and barberry toward the front.

The most pleasing hedges have rhythm and rest, which cannot be achieved by a hodgepodge of “one of these and one of those,” so it will pay to limit your selections and plant multiples of each. But if the deer pressure is extreme, don’t do it right away. Instead, plant a test garden of likely candidates and wait a year to see just how deer resistant they actually are. (Deer vary considerably in their tastes, and a plant that escapes unscathed in one place may well get lunched in another.) It’s frustrating not to plunge right in, but waiting is worth it when you’ll be buying — and planting — large numbers of new shrubs.


Deerproofing the Hedges

There are a number of low-tech, low-cost repellents, including human hair, soap, hot pepper, and garlic, all of which have some deterrent effect, but none of these household items are as effective as commercial spray-on products, especially the ones with bitter components, which have been formulated to be long-lasting.

These once-a-winter formulations are expensive compared to sweepings from the barber shop, but they cost a lot less than fencing or replacement trees.