With narrow, columnar trees for every yard

Dear Avant Gardener, I bought my first house this year and I’m looking forward to creating a yard full of plants that will feed both wildlife and my family. A good portion (about 15 by 30) is to the side of the house, with another two-story house immediately south, well established blue spruces on either end, and two big juniper bushes toward the front. I would love to fill it with shrubs for privacy from our neighbors (perhaps something like a dwarf serviceberry) and perennials to feed birds and pollinators. We’ll want a path of some type, but I don’t foresee a zone for sitting. Our local Prairie Moon nursery is going to be a great resource in choosing plants, but what should I be thinking about for structure and layout in such a narrow space? -– Erin, Minneapolis, MN

The side-yard conundrum! So many urban and suburban yards have narrow, shady areas on one or both sides. The instinct is to go small. But I suggest the opposite: Go tall.

You will look at this yard most often from your south-facing windows, so design it for the view from there. I recommend investing as much of your budget as you can in trees that are already eight to ten feet tall. That’s about the minimum height you’ll be able to see as you walk around inside your first floor. Additionally, when you walk into the side yard or glance at it from your front or back yard, tall, narrow trees will raise your eyes upward, making the space feel more expansive.

Tip: Large trees can be hard to find, so start searching soon; nurseries know now what they’ll have available in spring.

Privacy vs. a beautiful distraction

BTW, no planting solution will really provide privacy, because you don’t want to block either your or your neighbor’s windows. But seeing beautiful trees and the birds they attract from inside will cheer you up and draw you to the windows or, occasionally, outside. (For privacy, I recommend aluminum blinds, because you can adjust visibility and light levels; throughout each house, I use a single metallic shade — currently, brushed aluminum and ash metallic — of Bali Customiser Mini Blinds.)

Your biggest challenge will be siting trees artistically on the far side of the side yard so they’re centered in the view from your windows but are not in front of the windows of the house next door. Look for trees or tall shrubs with columnar, vase, or narrow, high canopy shapes and a full height of 15 to 30 feet and spread of less than 15 feet.

For example, you might put a columnar arborvitae cultivar like ​Thuja occidentalis 'Degroot's Spire'​ on either side of the neighbor’s window, then a quaking aspen (Populus tremeloides) on its own further down the wall. Or you could create a mini-grove feel, spacing five of one species — say, pagoda dogwood (Cornus alternifolia) – evenly along the neighbor’s wall. Five full-sized serviceberries would also be lovely; however, if your juniper bushes are true Juniperus, you risk Gymnosporangium fungus infection (see below).

Keep in mind that mature sizes often represent the biggest ever under optimal conditions. In nature, where they grow closely together, trees are smaller. I recommend similarly constraining their growth, planting your trees five to 10 feet apart.

Underplanting options

What else to plant on either side of the path will depend on your taste and budget. Just aim for lots of each species, rather than onesies and two-sies. A minimum of three of any shrub and nine of any perennial will contribute to a unified look. Here are some suggestions:

• If you’ve got enough budget, consider planting shrubs that will grow to four to six feet tall between the trees on the far side. You’ll have to be close to the windows to view these shrubs, but they’ll add structure, wildlife value, and sense of seclusion. I’d love to see red-twigged dogwoods (Cornus sericea) brighten your winters with their bright red bark.

• For fruits your family and wildlife will enjoy, plant elderberries (Sambucus nigra) on the sunnier (north) side of the path and lowbush blueberry shrubs (Vaccinium angustifolium) and perennial wild strawberries (Fragaria virginiana) on either side.

• Around the trees and any shrubs on the south-side of the path, plant a groundcover of sedges, ferns and woodland wildflowers as plugs or small plants. (I have not had much luck with seeds in shade and perennials tend to establish more slowly there.)

• On the closer, sunnier side of the path, save money and have fun by seeding right now with a meadow mix of grasses and wildflowers that likes part shade. You’ll take advantage of the winter for the necessary stratification (cold period) for many native seeds. Prairie Moon’s Pretty Darn Quick seed mix would be a great choice for this entire area. See my tips for direct seeding — including overseeding — ​here​. (Don’t worry, you can still plant shrubs into the seeded area in the spring.)

For the path, why not just keep a three-foot section of turf? It looks as if it’s thriving, It’s not doing any hard in itself without irrigation, fertilizer, or pesticides. It could be straight or, even better, a long arc or ess-curve.

Happy planning!

Dear Avant Gardener, My small one acre plot is my haven and heaven. I have over decades tried to make it more bird and bee friendly. Because of the high alkalinity most plants do not do well here. Do you know of any affordable seed packet collections that thrive in highly alkaline clay soils? After 30+ years I have gradually gone to container planting because the soil (even though amended every year remains hostile to most plants and trees I have tried)! — Robert

Yes! Although native plants prefer acidic soils as a rule, many thrive in a range of pHs. Those with deep tap roots are especially effective at breaking the densely-packed silt particles that make clay and hold water that can rot less robust roots. Several native seed companies offer special clay mixes, like the ​Conquer the Clay​ mix from Prairie Moon.

Once established, the root systems of these plants can exceed 6 feet deep! Even some of the more demure-looking species are strong enough to tap into the well of nutrients that lies 5-7 feet beneath the layers of clay. It's these tough tappers that allow flowers to bloom up to 10 feet above the surface, towering over what was once bare. — Prairie Moon Nursery

If you prefer single species to a meadow, just select individual species from the components of the mix, which includes most of my easy-to-grow from seed recommendations, available along with seeding tips ​here​.

One caveat: Deep taproot natives do not tend to transplant well, so you’re probably better off direct seeding than growing them in pots then transplanting.

— The Avant Gardener

P.S. I am eager for yard transformation questions to answer in this newsletter. Please send yours, with pictures.

Why, How, Wow!

Why?

Have you noticed I seldom write about treating plant diseases or infestations? That’s because the cure is often worse than the disease. In fact, dreaded holes in leaves are often evidence of healthy caterpillars on host plants. Shuddersome aphids are merely at the bottom of the food chain. And “organic pesticides” still kill (see ​The Myth of Organic​).

The key to healthy plants is “right plant, right place.” Choose your plants for the existing conditions – soil, sunlight, moisture, and so on. If a plant is not thriving, consider moving it. Or just cut it down (leave the roots unless it’s clearly diseased) and plant something else in its place.

I was soooo disappointed when spiny rust-colored galls appeared on my newly planted serviceberry. It was too close to an eastern red cedar. Sure, there are fungicides, but who wants to fool around with poisons? It might have lived on with the rust, but we decided to move it to the opposite side of the house and it’s doing fine, thank you.

Gymnosporangium rusts are a group of closely related diseases caused by fungi that infect both junipers (in particular red cedar) and woody plants in the rose family such as, but not limited to, apple, crabapple, hawthorn and quince. These fungi must infect both types of plants to complete their life cycles. …

The best way to avoid Gymnosporangium rusts is to not grow junipers (particularly red cedar) and susceptible rosaceous hosts close to one another. In urban settings where yards are small however, keeping both hosts adequately separated may be impossible. — ​Wisconsin Horticulture, University of Wisconsin​

How

Strikingly vertical trees punctuate a landscape. They are especially effective as pairs — think of Italian cypresses in medieval villages — or spaced close together in a row, as in an allée or along a fence. The columnar trees below are all cultivars of North American natives. (Researchers have found that changing the overall size or shape of a tree or shrub does not affect its wildlife value, as opposed to changing the size or shape of flowers.)

Reminder: It's easy to mistake an exotic for a native with a similar name, especially with cultivars. To check if a species is native to your area, look up its genus at the ​Biota of North America (BONAP)​. You can learn more about each cultivar below at ​Fast Growing Trees​; however, I recommend you source trees locally when possible.

Sweetgum (Liquidambar styraciflua) 'Slender Silhouette'

Armstrong Gold® Maple (Acer rubrum)

'Emerald Green' Arborvitae (Thuja occidentalis)

Golden Falls® Redbud Tree (Cercis canadensis)

'Little Gem' Southern Magnolia (Magnolia grandiflora)

'Taylor' Eastern Red Cedar (Juniperus virginiana)

Wow!

Pairs and rows of Italian cypresses squeeze greenery into small spaces in medieval villages, like this one in France. Although cypresses are sold in the U.S., cultivars of various native evergreens deliver the same impact while providing much more value for native wildlife.