LUSCIOUS LANDSCAPING

From Alaska & the White Mountains to my Garden

Lingonberry a plant of harsh, cold climates. I’ve seen the plants poking out of rocky crevices in Alaska and high in New Hampshire’s White Mountains, all of which makes all the more surprising the stellar performance of my plants in this hot summer. For years they sat quietly, growing slowly and slowly spreading; this summer, the plants took off, their underground stems reaching further than usual and aboveground stems sporting a very respectable crop. Or, I should say, crops, plural; more on that later.lingonberries in hand

Here in the U.S., lingonberries are little known and, when they are known, it’s as jars of jam. But merely utter the word “lingonberry” to someone Scandinavian and watch for a smile on their lips and a dreamy look in their eyes. Each year, thousands of tons of lingonberries are harvested from the wild throughout Scandinavia, destined for sauce, juice, jam, wine, and baked goods. A fair number of these berries are, of course, just popped posthaste into appreciative mouths.

Lingonberry in White Mountains

Lingonberry in White Mountains

Lingonberries have often been compared to their close relative, our Thanksgiving cranberries. But lingonberry fruits meld just enough sweetness with a rich, unique aroma so that the fruits — if picked dead ripe — are delicious plucked right off the plants into your mouth or mixed with, say, your morning cereal. As far as I’m concerned, cranberries are never palatable until doctored up with plenty of sugar and heat.

More Than Just Good Looks

As tasty as lingonberry is, I don’t grow it only for its fruit. Lingonberry also outshines its stateside relative in looks. The plants are pretty enough to have garnered a rating of 3, the highest possible, in my book Landscaping with Fruit.

Like cranberry, lingonberry grows only a few inches high and spreads horizontally to blanket the ground with evergreen leaves the size of mouse ears. While the onset of cold weather in fall turns Thanksgiving cranberry’s evergreen leaves muddy purple color, lingonberry leaves retain their glossy, green appearance, like holly’s, right through winter. Lingonberry under snowLingonberry could stand in well for low-growing boxwood — in a parterre, for example, a use first suggested in 1651 by André Mollet, the French gardener to Queen Christina of Sweden

Cute, urn-shaped blossoms dangle singly or in clusters near the ends of lingonberry’s thin, semi-woody stems. These urns hang upside down (upside down for an urn, that is) and are white, blushed with pink. They’re not the kind of blossoms that are going to stop street traffic, but are best appreciated where plants can be looked at  frequently and up close — such as in the beds along the path to the front of my house.Lingonberry flowering

If you miss the spring floral show, you get another chance because lingonberries blossom twice each season. That second show has now morphed into clusters of developing fruits that hang right next to clusters of fruits ripening from the first round of blossoms. Fruit yields are greater from the second flowering than from the first.Lingonberry old and new fruits

The pea-sized fruits a show in themselves, the bright red berries hanging on the plants for a long time, well into winter. Backed by the shiny, green leaves, they making a perfect Christmas season decoration in situ.

Soil Prep & Management: Obligatory but Easy

Lingonberry plants do need some special care. Hot summer temperatures aren’t ideal. My plants were originally near the east and north sides of my house. Those on the east side are now few and far between, perhaps helped along on the way out by the scratching of the ground beneath them by my chickens, now gone (replaced by ducks, who don’t scratch). The north side of the house, not as welcoming to the chickens because it’s my dogs’ hangout, is, of course, cooler.

All the soils that lingonberries naturally inhabit have good drainage and are extremely rich in humus (decomposed organic material), which clings to moisture. In addition to good drainage and abundant organic matter, lingonberries enjoy the same very acidic conditions — with a pH ideally between 4.5 and 5.5 — required by blueberries, mountain laurel, rhododendron and other kin in the Heath Family. These conditions are easily reproduced in a garden.

I created my bed of lingonberries, which is also home to lingonberry kin, by first checking the soil pH. If the pH is too high, digging elemental sulfur into the top six inches of ground can make it right. Three-quarters of a pound per 100 square feet in sandy soils, or 2 pounds per 100 square feet in heavier soils will lower the pH by one unit. Where soils are naturally very alkaline (pH higher than 8), such as in many parts of the western United States, soil needs to be excavated at the planting site and replaced with a fifty-fifty mix of peat moss and sand. Alternatively, this mix could go into containers plunged into the ground up to their rims. In wet areas, build up mounds of soil and peat, and plant the lingonberries on the mounds, which keeps their shallow roots above water level.

I set my plants at two foot by two foot spacings which plants fill in to form a solid mat over the ground. Young lingonberry plantEvery year, in late fall, I scatter wood chips, sawdust, or shredded leaves over the plants, enough for an inch or two depth. Sifting down through the leaves and stems to keep the ground cool and moist, to prevent frost from heaving plants in winter, to maintain high humus levels in the soil, to provide some nutrients, and to buffer soil acidity. Every few years I check acidity, and sprinkle sulfur on the soil, as needed.

Enjoy!

Beyond needing mulching and having their soil acidity monitored, lingonberries are carefree plants. My main “job” is harvesting the berries. No need even to rush picking or eating them. They keep well on or off the bush, in part because they contain benzoic acid, a natural preservative. Refrigerated, the harvested berries keep for at least eight weeks. In nineteenth-century Sweden, lingonberries were kept from one year to the next as “water lingon,” made by merely filling a jar with the berries, then pouring water over them.

My main problem with lingonberries is, at the end of the growing season, deciding whether to harvest and enjoy the berries immediately and enjoy only the glossy, green groundcover or whether to leave the berries on into winter and enjoy the look of the glossy green groundcover livened up with red berries. Or to split the different, occasionally harvesting some of the fresh berries all through winter.

Lingonberry and lowbush blueberry in fall

Lingonberry and lowbush blueberry in fall

MY BICOASTAL PLANT

A Tree Takes a Plane Ride

I managed to pack lightly for a journey, many years ago, to the West Coast, toting along only an extra pair of pants, a couple of shirts, and a few other essentials. But on the return trip, how could I resist carrying back such bits of California as orange-flavored olive oil and chestnut-fig preserves? The most obvious bit of California that I brought back was a potted bay laurel plant (Lauris nobilis), its single stem poking out of my small backpack and brushing fragrant leaves against the faces of my fellow travelers.

standard bay, rosemary, citrus

Bay, with its subtropical pals, rosemary and citrus

Not only did the bay laurel bring a bit of California to my home, but also traditions dating back thousands of years from its native home along the Mediterranean coast. Ancient Romans crowned victors with wreaths of laurel and bestowed berried branches upon doctors passing their final examinations. (The word “baccalaureate” comes from bacca laureus, Latin for “laurel berry”.) Bay laurel was sacred to Apollo, so was planted near temples. 

Although bay laurel can grow fifty feet tall, my plan was to develop this plant into a small tree with a single, upright trunk capped by a pompom of leaves. The Mediterranean climate is characterized by hot, dry summers, and cool, moist winters. Since the plant is hardy only to about fifteen degrees Fahrenheit, I had to grow it in a pot. The plant is allegedly a rich feeder, but my plants grows fine in my homemade potting mix which contains a healthy portion of compost and — for some extra oomph — some soybean meal.

The potted tree decorates the house in winter, the terrace in summer, and provides fresh bay leaves for soups and other dishes year-round.

A Winter Home

It is in winter that my plant realizes just how far it is from its Mediterranean home. Winters in its home lands are typically cool and moist. Winters inside a northern home are typically warm and dry. Since cool rooms are moister than warm rooms in winter, the cooler the room the better, preferably below fifty degrees. My bay laurel has wintered well either in sunny window in a cool room or near a bright window in my basement, where temperatures are very cool. The warmer the temperatures, the more light bay laurel needs.

The other challenge to my bay tree has been scale insects. They sit along leaves and stems under their protective shell as they suck sap from the plant. scale insects on barkActually, it’s more of a challenge to me because the plant tolerates scale reasonably well. Once moved outdoors in spring, the plant soon recovers from the attack and its resident scale population, either from the changed environment or from predators, subsides.

The problem for me is that the insects exude a sticky honeydew that drips onto furniture and the floor. A sooty black fungus then feeds on the honeydew.

This summer I’ve taken a more active role in thwarting scale by spraying the plant weekly with horticultural oil, which is nontoxic to humans and soon evaporates.

Lollipops

Bay laurel can be trained to any number of shapes such as a pyramid, cone, or globe, with these shapes beginning at ground level or capping a long or short piece of trunk.

Right from the get go, I chose to grow my tree as a “standard.” “Standard” has many meanings both in and out of horticulture, so let’s first get straight which kind of “standard” we are dealing with: Here, I mean a naturally bushy, small plant trained to have a clear, upright stem capped by a mop of leaves. A miniature tree. Standard evergreens along front pathIn the world of gardening, people are divided over how they feel about “standards.” Some gardeners love them, others will have nothing to do with them.Standard bay laurel

(A “standard” apple tree is one grafted to a rootstock that does not confer any dwarfing.)

For training my lollipop-shaped bay tree, I allowed only a single stem to grow straight upward, and then pinched off any side shoots that developed. When the trunk reached three feet in height, I pinched out the tip to cause branches to form high on the stem. I kept this up, pinching branches and then their branches, to cause further branching, thus forming a dense head. (I devote a whole chapter to standards in my book The Pruning Book.)

Training a standard

Training a standard (rosemary, in this case)

Or, in an illustration (from The Pruning Book):Steps in making a standard

Ongoing care of the tree entails pruning and pinching to keep the mop head to size, and root pruning and repotting the plant every couple of years or so. The time to do any trimming to keep a plant in shape is mostly just as soon as the new shoots mature and stop growing in early summer.Pruning bay laurel

A few years ago, I decided that my tree was too tall and unwieldy; I wanted a shorter standard. Easy: I just lopped the whole plant to the ground and started again. With an established root system fueling new growth, I was able to develop the new lollipop quickly.Standard bay & rosemary

All this pinching and pruning yields fresh bay leaves, which find their way into the kitchen. The fresh leaf has a strong flavor, and one cookbook suggests (and I now confirm this) using one leaf for a dish to serve four people. The aroma of the fresh leaf is more than just strong; it actually has a different quality than that of the dried leaf. The fresh aroma is almost oily, to me somewhat reminiscent of olive oil — how California-ish!

A BACTERIA TO THE RESCUE

A Cabbageworm is a Cabbageworm is a . . . Not!

A few weeks ago, one or more of the few species of “cabbageworms” began munching the leaves of my cabbage and Brussels sprouts plants. They ignored kale leaves, thankfully, because it’s my favorite of the three.

Cabbageworm damage

A laissez fair approach would have left the cabbages and Brussels sprouts mere skeletons, so I had to take some sort of action.

For the record, “cabbageworms” are actually not worms, but a few species of caterpillars all classified — and this is important — in the order Lepidoptera. Here’s the lineup: A cabbage looper arches its back when moving, and is light green with a pale white stripe along each of its sides and two thin white stripes down its back.

Cabbage looper

Cabbage looper

A diamondback moth larvae is 5/16 inch long, yellowish-green, and spindle shaped with a forked tail.

Diamondback moth larva

Diamondback moth larva

A cabbageworm (yes, one kind of cabbageworm is named “cabbageworm”) is one-and-a-quarter inches long, velvety green, and has a narrow, light yellow stripe down the middle of its back.

Cabbageworm & cross-striped cabbageworm

Cabbageworm & cross-striped cabbageworm

A cross-striped cabbageworm is 3/4 inch long and bluish-gray in color with many black stripes running cross-wise on its back, below which a black and yellow stripe runs along the length of its body.

Natural Control

I put an end to whichever “worms” were the culprits, and was able to do so without resorting to any chemical spray, by spraying the plants with Bt. Bt is the commonly used abbreviation for Bacillus thuringiensis, a bacterium that causes disease in certain insects. After ingesting Bt, a cabbageworm becomes sick, stops eating, and dies. Since the Bt I sprayed is toxic only to lepidopterous insects, it doesn’t pose any danger to other creatures, such as birds, cats, dogs, humans, and even other insects.

The insecticidal properties of Bt have been known since early in the twentieth century, when the bacterium was discovered as a silkworm pest by Japanese researchers. (Silkworms are also Lepidoptera.) The originally discovered strain of this bacteria is toxic only to caterpillars, which are larvae of butterflies and moths, and was first used purposefully to control the European corn borer in Europe in the 1930s. Interest in Bt waned in the late 1940s, when nerve gases used during World War II led to the development of new types of chemical pesticides. In the 1960s, agricultural scientists finally began to take a second look at Bt.

Many strains of Bt have been isolated. The ones for cabbageworms and other Lepidoptera are  Bt aizawai and Bt kurstaki. Thuricide labelThe strain Bt var. israelensis is toxic to larvae of black flies and mosquitoes. Another strain, Bt var. san diego, is toxic to Colorado potato beetle larvae.

All these strains of Bt are available commercially. The bacteria are packaged in a dormant condition either as a dry powder, a liquid suspension, or, in the case of Bt var. israelensis, a slow release ring that is floated on water to kill mosquito larvae. Bt goes under a number of brand names which don’t give a hint of the pesticide’s ingredients, so read the label to make sure of what you are buying. The product I use goes under the trade name Thuricide.

Bt is a living organism, so I store it in such a way as to prolong its viability. (Here on the farmden, Bt resides in the back of the refrigerator, which is generally a strong no-no for pesticides. (But Bt is nontoxic, and there are no children in the house.) Kept cool and dry, the bacteria will remain viable in its container for two or three years. Bt works quickly enough so I can check for discolored, blackened, or shriveled larvae the next day to see if the spray is still viable.

But . . .

Is there some trade-off that must be made when using this apparently benign pesticide? Yes, insect pests can develop resistance to Bt, just as they do to chemical pesticides. Resistance is most likely from continuous, repetitive use of any single pesticide, or different ones with the same mode of action.

This problem, with Bt, has been exacerbated since almost 500 million acres of crops, mostly field corn and cotton, have been genetically engineered with insecticidal Bt genes. It’s equivalent to the field being constantly sprayed with Bt. Some resistance has been found.

In my garden, I apply Bt at the recommended rate, only to afflicted plants, and only when a pest problem gets sufficiently out of hand to warrant treatment. 

There’s another good reason for careful use of at least the original strain of Bt. Since this strain is toxic to caterpillars, indiscriminate use could substantially decrease the caterpillar population and, hence, the numbers of moths and butterflies. My distaste for the celeryworm, which has a voracious appetite for carrot, celery, and parsley leaves, is tempered by the beauty of its adult form.

Celeryworm

Celeryworm

Surely the elegance and grace of the adult form, the black swallowtail butterfly fluttering about the garden, adds as much beauty as a marigold or rose.

Black swallowtail butterfly

Black swallowtail