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Author: Russell Stafford

Hortiholic and plant evangelist, Russell Stafford, transplanted his first perennial at age 7 and thereby began a lifelong plant addiction. He is the founder and custodian of Odyssey Bulbs (and Odyssey Perennials), an online nursery specializing in cool and uncommon plants. Russell also works as a horticultural consultant, freelance writer (Horticulture and The American Gardener magazines), and garden editor. He formerly served as Curator and Head of Horticulture at Fernwood Botanic Garden in Niles, Michigan and as the Horticultural Program Coordinator at the Center for Plant Conservation, then located at the Arnold Arboretum in Jamaica Plain, Massachusetts. His academic degrees include a masters in forest science from Harvard University.

8 Best Watering Practices for Plants

Watering flowers with a watering canPlants need moisture to survive and thrive (as your plants will be all too willing to demonstrate if you’re too sparing with the watering can).  Give their roots enough water, and their breathing leaf pores (known botanically as stomata) can remain open for business, drawing up nutrient-rich water from the soil and taking in carbon dioxide from the air.  Give them too little water, and they will languish.

But as with most good things, too much water can be problematic as well, leading to poorly aerated soil and suffocated roots.  Here are the eight best watering practices for plants to help your plants keep happily hydrated (and not deathly dry or sickeningly soggy) this summer and beyond:

Fafard Premium Natural & Organic Compost Blend pack
Fafard Garden Compost Blend is a great soil amendment for increased water retention.

1. Water New Plantings Well

New plantings require special attention, especially in the heat and drought of summer.  Root balls of container-grown plants are almost always coarser and faster-drying than the soil into which they are planted.  Consequently, they can become dust-dry even when the surrounding soil appears to be sufficiently moist.  Monitor them frequently, watering when necessary.  Bare-root and balled-and-burlapped plants lose most of their roots during the digging and transplanting process and are thus at even greater risk of drying.  Plant them in spring before leaf-out (or in fall when the air is cooler and the soil is still warm), and water them regularly until they’re established.  In all cases, apply 2 or 3 inches of bark mulch to new plantings to retain moisture and to deter soil compaction.

2. Maximize Root Contact

Loosen the outer roots of root-bound container-grown plants, to allow contact with the surrounding soil.  Mound soil around all newly installed plants (without covering their stems) to increase water retention at the root level.

3. Amend Clay-Rich Soil

In clay soil, planting holes can become root-drowning bathtubs, and the fine clay particles actually make it harder for roots to access much-needed water during drought periods.  Add water-holding organic matter (such as Fafard Premium Natural & Organic Compost Blend) to gradually improve the texture and drainage of heavy soil while increasing water availability to plants.

4. Know Your Plant’s Watering Needs

Know the moisture requirements of plants before you buy and install them.  Many ornamental plants from dry-summer regions such as the Mediterranean and Central Asia are intolerant of damp warm-season conditions.  Conversely, moisture-loving species such as golden groundsel (Ligularia dentata) and swamp azalea (Rhododendron viscosum) begin to wilt at the slightest hint of drought.

Purple and yellow flowers
Well-watered plants are easy to spot due to their good health.

5. Keep Trees and Shrubs Watered in Drought

Even established shrubs and trees may need watering during prolonged drought.  Deep watering is not necessary and can be counter-productive, given that most roots are in the upper few inches of soil.  Rather, water frequently and shallowly, to keep the upper, most drought-susceptible roots from drying.  “Deep” watering may cause plants to produce new, succulent growth, thereby compromising their drought resistance.  Mulch (see above) will lessen the likelihood of drought stress in established plantings, just as it does in new ones.

6. Water in the Morning

Water in the morning before the heat of the day, or at other hours on cloudy days.  Use a hose and wand or watering can to directly irrigate recently installed plants.  Soaker hoses, drip systems, and other irrigation methods that directly contact the soil are ideal for established plantings.  Sprinklers waste water.

7. Know How to Water Potted Plants

For potted plants: water when the potting mix reaches the appropriate level of dryness (typically when the surface of the mix is dry).  Alter watering frequency as necessary for plants from arid or damp climates.  Species native to tropical forests and other humid habitats may benefit from misting, or from being placed on a pebble- and water-filled humidity tray.  Use a suitable soil mix; for example, many orchids prosper in a bark-rich mix such as Fafard Orchid Potting Mix, and moisture-loving species will appreciate a humus-rich medium such as Fafard Natural & Organic Potting Mix.  Relatively deep, narrow pots drain (and dry out) more rapidly than shallower, wider pots.

8. Keep Pots Gravel Free

Contrary to popular gardening myth, layering gravel or other coarse material beneath the potting mix does not increase its drainage, but rather decreases its aeration and depth.  This practice is detrimental rather than beneficial for most plants.

Bold, Tropical Colocasias

Giant Colocasia
Thai giant Colocasia is as bold and tropical as it gets! (Photo care of Logee’s (www.logees.com))

Is your garden (or greenhouse) going tropical this summer, with bold leaves and eye-catching hues?   Then you’ll doubtless want to accent it with a plant (or three) of Colocasia esculenta.  Commonly known as elephant ear, this frost-tender, warm-season perennial produces broad, prominently lobed, heart-shaped leaves that can indeed reach pachydermic proportions, giving it obvious cache for tropical-flavored planting schemes.  It also comes in a wide range of colors and sizes, suggesting other design possibilities.

Colocasia 'Illustris'
Colocasia ‘Illustris’ is a classic variety with black-stained leaves. (Photo by Jessie Keith)

Elephant Ears

Its suitability for eating is what first brought Colocasia esculenta into cultivation some 10,000 years ago.  Today, it remains a dietary mainstay throughout much of the tropics, represented by hundreds of varieties and nearly as many common names (including taro, dasheen, eddo, and cocoyam).   As a comestible, it is prized more for its plump, starchy, underground tubers than for the long-stalked leaves that arise from them (although the leaf blades and petioles are sometimes consumed).

Most ornamental elephant ears, on the other hand, possess little food value, having been selected for looks rather than flavor.  Additionally, almost all varieties (culinary and otherwise) require cooking to neutralize the acrid, needlelike molecules that lace their tissues.  Uncooked tubers or leaves can cause intense discomfort if ingested.  So look; don’t munch!

Electric Blue Gecko
Electric Blue Gecko™ is a real beauty with its textured, all black leaves. (Photo care of Logee’s)

If what you’re looking for is something in an extra-large, an elephantine Colocasia may be just the ticket (are 3-foot leaves on 3-to 6-foot stems big enough for your tropical paradise?).  Gargantuan cultivars include ‘Fontanesii’, whose dark green leaves have deep purple stems, veins, and margins; ‘Coffee Cups’, with theatrically folded, olive-green, purple-veined leaf blades atop black-purple stems;  and ‘Burgundy Stem’, named for its stem color but equally remarkable for its pale green, chalky-veined, purple-suffused leaf blades. (Then, of course, there is the monstrous green-leaved Thai giant (Colocasia gigantea)). Of somewhat smaller size but equally dramatic coloration are numerous other selections such as ‘Illustris’ (black-stained, pale-veined leaves); ‘Black Magic’ (with black staining enveloping the entire leaf); ‘Mojito’ (apple-green, purplish-stemmed blades with black-purple mottling and flecking); and Electric Blue Gecko™ (slender, textured, pure black leaves with a metallic overlay).

The dwarf of the tribe, Colocasia affinis, is also well worth growing for its purple-flushed, 6-inch-long leaf blades.  It’s usually represented in cultivation by ‘Jenningsii’, a deep charcoal-colored form with pale green veins and ash-gray midribs.

Black Magic leaves
The soft black leaves of ‘Black Magic’ add depth and interest to beds and borders. (Photo care of Logee’s)

Alocasia

You might also want to take a look at the many species of Alocasia, a genus once included in Colocasia.  Members of this elephant-ear clan typically bear large, corrugated, arrowhead-shaped leaves of metallic hue.  The foot-long, deep green, heavily puckered leaf blades of Alocasia cuprea have a pewter overlay and sunken, burgundy-purple veins.  Alocasia x amazonica brandishes gleaming, wrinkled, almost black-green leaves with silver-white veins and heavily scalloped margins.  A few alocasias rival or even surpass the largest colocasias in size, with some selections and hybrids of giant taro (Alocasia macrorrhizos) producing immense leaves (as well as a trunk-like stem) from massive tubers.  Giant taro’s close relatives A. odora and A. portei are of similarly jaw-dropping stature.

Fafard Ultra Container Mix with Extended Feed pack
This mix contains Moisture Pro™ water holding crystals, to maintain mix moisture for longer.

Growing Elephant Ears

To grow elephant ears worthy of the name, plant them a few inches deep in ample sun and fertile, humus-rich soil after the ground has warmed (tomato-planting time is ideal).  Amend the planting hole with an organic medium such as Fafard Premium Natural & Organic Compost Blend, liberally so where soils are sandy or heavy.  These evergreen to semi-evergreen perennials die back in fall in areas that experience frost, returning in spring if their tubers don’t freeze.   Many cultivars will survive USDA Zone 7 winters under a deep leafy mulch.  If necessary, plants can spend the winter indoors, either in pots (in a warm sunny niche) or as dormant tubers (stored in dry potting mix in a cool dark well-ventilated room).  Or grow them year-round in a sunny warm greenhouse.  A moist, fibrous, well-drained growing medium such as Fafard Ultra Container Mix works beautifully.

Colocasias and their kin achieve their greatest grandeur in regions with humid, frost-free climes (think southern Florida).  A few varieties will even spread by runners, forming veritable herds of elephant ears.  From the steamy Deep South to the wintry Far North, no plants are better at bringing a taste of the tropics to the garden and greenhouse.

Growing Cranberries (for Nantucket Cranberry Pie)

 

Growing Cranberries (For Nantucket Cranberry Pie) Featured Image

Despite its association with bogs, both in commercial cultivation and in nature, cranberry requires no such sogginess in home gardens, prospering in highly acidic, humus-rich soil that doesn’t dry out. The wiry, carpeting, slender-leaved stems are perfect for covering small slopes, walls, and hollows, and are particularly effective near paths and patios, where the fine-textured foliage, small pinkish early-summer bell-flowers, and showy red berries can receive the adulation (and harvesting) they deserve. Individual plants typically mature at 6- to 8-inches tall and 2- to 4-feet wide.

Cranberry Varieties

cranberry USDA
A cranberry in full fruit (Image care of USDA, ARS)

Most cultivated cranberry (Vaccinium macrocarpon) varieties come courtesy of the cranberry industry, which has selected them for fruitfulness rather than for ornamental characteristics. A notable exception is ‘Hamilton’, a dwarf cultivar that slowly evolves into a dense, lustrous, foot-wide hummock, adorned in fall with normal-sized berries that loom large amid the tiny, congested leaves. This beauty merits the company of other small, special ornamental plants, the sort that dwell in rock gardens or troughs. It also works well as a solo container plant. Give it a good potting mix amended with peat moss, Fafard Premium Organic Compost, and a dollop of garden soil.

Although most commercial cranberry cultivars (such as ‘Stevens’) offer nothing exceptional in the way of habit and leafage, they are well worth a place in ornamental plantings, functioning as small-scale ground covers and offering a bumper crop of berries as a bonus. Where happy, they produce as much as a quarter-pound of fruit per square foot (expect some losses from insects and fungal disease). Add peat-rich Fafard Premium Organic Compost to the soil to boost soil organic content, if necessary, and elemental sulfur to increase acidity.

Cranberry Relatives

Lingonberry
Lingonberry has glossy evergreen leaves.

Widely planted in Europe for food and for ornament, lingonberries (
Vaccinium vitis-idaea) have yet to establish a substantial beachhead in North American gardens. Perhaps this is because the most vigorous and easily grown forms occur in northern Eurasia, where they have long been cultivated for their cranberry-like fruits. Most European lingonberries spread relatively rapidly into dense, bushy, 8- to 12-inch-tall clumps. Clusters of pale pink, urn-shaped flowers open in late spring and summer, ripening to tomato-red fruits in late summer and fall. Cultivars abound, including the popular Koralle Group, which flower and fruit copiously on compact, 4- to 6-inch tussocks, and ‘Red Pearl’, whose large, quarter-inch- to half-inch-wide berries are borne on vigorous, wide-spreading plants with upright, 12-inch-tall branches.

Somewhat more adaptable than cranberry, European lingonberry takes readily to acidic, humus-rich, well-drained soil in full to partial sun, where it excels as a refined groundcover. Plant more than one variety for heaviest fruiting. Compact forms, such as the Koralle Group, make good subjects for containers (give them a highly organic potting mix amended with peat and garden soil).

The North American edition of lingonberry (Vaccinium vitis-idaea ssp. minus) inhabits bog margins and mountaintops from the northernmost United States to the Arctic Circle. Smaller, less fruitful, balkier, but more elegant than its European kin, it’s an ideal subject for rock gardens and large troughs in regions where summer temperatures rarely exceed 90 degrees F.

In cooking, lingonberries play the same roles as cranberries, adding color and zest to preserves, sauces, and baked goods. They also freeze well, emerging from the fridge to bring a taste of fall to the midwinter table. Offering year-round beauty in the garden and fall-to-spring flavor in the kitchen, both of these little Vaccinium keep bringing joy long after the holiday cheer has ended.

Recipe: Nantucket Cranberry Pie

Nantucket Cranberry Pie
Nantucket cranberry pie is an easy and delicious fall pie.

A fast, easy pie of New England fame, the Nantucket cranberry pie has many variations, and all are delicious. The bottomless pie is covered with a nutty crumb topping and baked to perfection. Almond extract gives it a needed aromatic boost.

  • 2 cups cranberries
  • 3/4 cup chopped walnuts
  • 3/4 cup sugar
  • 1 cup flour
  • 1 cup sugar (1/2 cup  for tart pie)
  • 1 stick melted butter
  • 2 lightly beaten eggs
  • 1 tsp. almond extract
  • 1/4 teaspoon salt (optional)
  • 1 pat butter

Directions
Preheat oven to 350 degrees F. Thoroughly grease a pie pan with a butter pat. Place the cranberries at the bottom of the pan then sprinkle with the walnuts and 2/3 cup sugar.

In a bowl, gently stir together the flour, 1 cup of sugar, melted butter, eggs, almond extract and salt in a mixing bowl. Evenly pour the batter over the cranberries and walnuts. Bake the pie for 45 to 50 minutes.

Allow it to slightly cool before cutting. Serve the cooled pie with vanilla ice cream or whipped cream spiked with ginger. Top it with chopped candied ginger, if you like.