Oooh, that awful dry air in winter!

Houseplants and humidity

By Amy McDowell

When I was in charge of watering inside the dome at the Des Moines Botanical Center, I watered more than just the plants. I also soaked the concrete walls and pebbled paths. The plants, screaming for moisture, needed more than just a drink of water—they needed high humidity like the tropical rainforests of their origins.

During these cold winter months, the dry outside air is sucked into our furnaces, heated, and pumped through the heat vents throughout our homes. And just as we suffer with dehydration such as thirst, dry, itchy skin, tired, burning eyes and tender sinuses, our houseplants are suffering with dehydration that shows itself as curling leaves, dry brown leaf tips, yellow leaf margins, shriveling, wilting, bud drop and limp, weak growth.

The water that houseplants take up through their roots is used for growth, but much of the moisture is released, or transpired, through tiny holes in the stems and leaves called stomata. Winter air pumped through our furnaces is so dry that it rapidly taxes houseplants beyond their capacity. There are a number of things you can do to raise the humidity level and aid plants, and it doesn’t even require watering your walls and floors.

·        Humidifiers are the simplest and most effective method to raise humidity.
·        Group plants close together so they can benefit from each other’s transpired moisture.
·        Make pebble trays. Fill sturdy plant saucers with pebbles and water and place them around your houseplants. The pebbles create more surface area than just a dish of water so it will evaporate quickly.
·        Turn down the furnace. Plants will transpire less moisture if the furnace isn’t running as often. Also, keep plants away from heat vents and drafts.
·        If the kitchen or bathroom is bright enough, move plants there, where humidity is often higher than the rest of the house.
·        Misting plants is the least effective option. It is a short-term, temporary solution that must be repeated frequently throughout the day to even make a difference. In addition, water droplets on the leaves may lead to disease.

Aaahhh, those bloomin' indoor vines!

Blooming indoor vines

By Amy McDowell

The Linnaean House at the Missouri Botanic Garden is the most enthralling building I have ever set foot in. It is a brick-sided greenhouse built in 1916, proudly touted as the oldest continuously operating greenhouse this side of the Mississippi River. A brick path snakes through the center of the earth floor and plants on both sides of the path sink their roots directly into the ground. Vines clamor up the brick walls inside and outside the building. When the large wood-frame windows are left open in the summer, the scents of camellias and jasmine wisp in and out.

The earthen floor anchors plants and gives my soul an indoor soil connection far beyond potting soil in containers. Planting beds in the dome at the Des Moines Botanical Center are similar, but the scale of the Linnaean House creates an intimate, homey atmosphere. If only I could live in such a building.

I am left to recreate the divine environment on a pot-bound scale, but a handful of blooming vines cooperate with the conditions in my home. The following tender vines are some of the simplest. They require very bright light, like that in a southern- or eastern-facing window, and are content with average home temperatures and humidity. Most will bloom all winter with regular water, little fertilizer and an occasional trim. Spray to keep the bugs at bay. Once a month, use insecticidal soap or mix your own with a drop of dish soap and a teaspoon of rubbing alcohol in a 16-ounce spray bottle filled with water.

Black-Eyed Susan Vine (Thunbergia alata) originally bloomed golden with a dark eye. I grew it in that loud clashy color, but now they are available in tamer citrus colors, pink blush and pure white. The new colors look great beside the cool colors of Browalia (B. speciosa major) and trailing Lobelia (L. erinus). Browalia blooms with 1-inch blue stars all winter, and the Lobelia has dainty dark purple flowers.

Other vines that bloom indoors include smelly Lantana (L. montevidensis), ivy geranium (Pelargonium peltatum), red-and-white glory bower (Clerodendrum thomsoniae), finicky Fuschia (F. magellanica gracilis), delightfully fragrant snail vine (Phaseolus caracalla) and fan flower (Scaevola aemula).

Trees and Construction

Building your dream home on that wooded lot

By Amy McDowell

Wooded residential lots cost thousands more than treeless lots, but if those trees aren’t protected during construction, they can be severely damaged. Often the damage isn’t visible and the slow physiology of trees means they may live for four to seven years after construction crews have left the site, slowly spiraling into decline and finally death.


Soil compaction from heavy equipment and building materials is the most common damage. Ninety percent of a tree’s roots are within the top twelve inches of soil. Soil compaction may crush or tear the fine roots, but the loss of air space within the soil profile can be long lasting and even more devastating. Soil organisms can take decades to loosen compacted soils and return them to a healthy environment for tree roots.

The most important step to protecting the trees on your building lot is to ring them with a barrier that is not easily moved by construction crews. Metal stakes and bright orange snow fence works well. Place the barrier at least one foot from the base of the trunk for every inch of trunk diameter. For example, a tree with a two-foot diameter trunk must have a barrier at least 24 feet from the trunk.

Even after construction is complete, continue to guard the root zone. Don’t let a finish grader add or remove soil within the barrier zone. If you seed or sod the new lawn, use care not to drown the tree by irrigating too frequently. After the turf is established, water no more than once or twice a week.

A three-inch-deep mulch ring around the tree will protect the trunk from mower and string trimmer damage, and the wider the ring the better it is for the tree’s roots. Some arborists say a mulch ring that runs clear to the drip line of the branches would be a tree’s dream-come-true, although they realize that much mulch is unrealistic for most homeowners.

For large construction sites with complicated traffic patterns around trees, you might want to consult with an ISA certified arborist on how best to protect the trees. Information is available at www.isa-arbor.com or 800-ISA-TREE.

What Birds Want

Feeding our Feathered Friends

By Amy McDowell

When we moved my husband’s bedridden grandpa into a nursing home, we hung a bird feeder outside his window. Then each time family members visited him, they filled his feeder. His care center was in Polk City, and flocks of goldfinches visited the feeder every day.

He was unable to talk after suffering a stroke, but he would often point out the window at the feeder and smile tenderly. From his bed, he could see the TV and the bird feeder, and although watching TV passed the time, watching the birds obviously gave him great joy.

Grandpa is not the only one who enjoys feeding birds; more than 60 million people in the U.S. spend nearly a billion dollars a year on bird seed, and that figure does not include feeders or accessories like shepherd hooks and squirrel baffles.

What Birds Want


The most popular seed among birds is black oil sunflower seed, according to a 1980 report compiled by the U.S. Fish and Wildlife Service. They watched 13 different kinds of birds choose seeds from specially-designed feeders and found that all of them, including goldfinches, cardinals, chickadees, mourning doves, purple finches, and tufted titmice, chose black oil sunflower seed above all other seeds. The black oil sunflower seeds beat out striped sunflower seeds, red and white millet, sunflower hearts, cracked corn, peanut hearts, safflower seed, and milo.

Suet is popular among insect-eating birds like woodpeckers, robins, and wrens. Store-bought suet cakes are inexpensive and simple to slip into cage-style feeders. Many people make their own suet cakes, and recipes abound online. Most recipes include fresh ground suet, peanut butter, cornmeal, and a mixture of nuts, raisins, and seeds.

The birds will appreciate fresh water. During the winter you can use a heated bird bath or insert a heater into the bowl of your bird bath to keep the water thawed. A cheaper idea is to dump the ice every day and fill the bird bath with warm water. Of course, this won’t work with a heavy concrete birdbath, and it won’t stay thawed for long, but the birds will appreciate your efforts.

The leanest time of year for birds is spring, because their natural food sources from the previous season are gone and plants are not setting seed or producing berries in the current season yet. The months of March through June are more crucial than the winter months.