Category: Outdoors

Which plants are making you sneeze

If you suffer from spring allergies, this would be a good time to know what plants are affecting your comfort. Right now, many trees are dumping their pollen. Most trees are wind-pollinated and produce lots of pollen. They depend on the wind to move pollen around — and up your nose.

Although some trees and shrubs produce both male and female flowers, many are dioecious, meaning that male and female flowers are on separate plants. It is thus to their advantage to produce their (insignificant-looking) flowers and lots of pollen before the leaves get in the way. Which for me is right now. Showy flowers do not necessarily mean that trees like catalpa are low on the aggravation index (they are rated 8 of 10 on the index), but others like magnolias are lower. Both of those are pollinated by insects.

Of the trees, male poplars are among the worst — and in my area, they are just starting to bloom. Other culprits include willows, birches, oaks and some maples, but not all. If you are buying trees, look for trees that have separate male and female plants (as opposed to both on one). Always buy the female specimen if you can, as it is the males that produce the pollen and cause the allergic reactions. Not all plant tags will tell you if the plant is male or female, but good nurseries may know.

Very popular in the landscape industry right now is the Hakuru nashiki willow. It has tri-colored (green, white and pink) leaves in June and is sold either as a multi-stemmed shrub or as a “standard.” Standards are created by grafting branches on the top of a straight, bare-of-branches stem that is generally about 4 feet tall. As far as I know, Hakuru nashiki willows are all female, so they do not create the pollen that a pussy willow produces.

Want a nice pussy willow? Not all are bad for the allergy-prone. It is worth consulting a book like Tom Ogren’s Allergy-Free Gardening that lists trees and flowers species by species (and often with cultivars) with their potential for making you miserable. Ogren’s book lists “Weeping Sally” as a pussy willow with the lowest rating for causing allergies, while the male forms of white willow are among the worst rated. Even so, many of the males are sold as named cultivars for decorative purposes.

Not all pollen is created equal. Each spring I notice all the yellow pollen dropped on my car by pine trees. Pines produce huge amounts of pollen, but it is waxy and not very irritating to your nasal membranes. And it’s heavy, so it doesn’t fly far.

After the trees do their thing, along come the grasses. The seven worst offenders are introduced species of grass, including orchard grass, bluegrasses and timothy grass, which is commonly grown for animal feed. Grasses are wind-pollinated, and their pollen can float long distances. Your lawn should not be a problem so long as you never let the grass get tall enough to blossom. But fungal spores in the lawn can cause allergic reactions and can be stirred up by mowing, so if you get hay fever, you have a good excuse to get your spouse or kid to do the mowing.

Flowers with flashy form generally are not significant allergy-producers. Tulips, delphinium and peonies are obviously trying to get attention. They are the flirts — and insect-pollinated. Others such as hostas are among those least likely to cause an allergic reaction.

According to Lucy Huntington in her book Creating a Low-Allergen Garden, members of the daisy family have flowers that are insect-pollinated, but their pollen is highly allergenic to most sufferers. Chrysanthemums, asters, marigolds and zinnias can bother folks with allergies. I suppose that is particularly the case if you enjoy sniffing their scents. She also suggests avoiding geraniums (Pelargonium hybrids), strawflowers, dahlia hybrids, foxglove, sunflowers, nicotiana and cosmos.

Huntington’s book is full of lists and suggestions for low-allergen plants. Here are some of her suggestions for plants suitable for people with pollen allergies:

Annuals: Snapdragons, petunias, annual phlox, scarlet sage, purple salvia, pansies, bacopa, California poppies, nasturtiums and verbena

Perennials: columbine, astilbe, bellflowers, bleeding heart, delphinium, daylilies, Siberian iris, peonies, oriental poppies, penstemon, garden phlox, Jacob’s ladder, hollyhocks, alliums, globe flower, lady’s mantle, coral bells, catnip, hosta, foamflower and periwinkle.

The good news is this: Pollen is generally released in the morning, and by evening much of it has settled down, so evening should be a better time to garden. And rain knocks the pollen out of the air, so run outside and pull weeds after a nice downpour. You don’t have to cut down the culprits, and wearing a Covid mask will help if pollen is really bugging you!

Featured photo: Catalpa blossoms are showy and insect-pollinated but still can cause hay fever. Courtesy photo.

Contemplating potential garden improvements

This is a good time to look carefully at your garden, and to decide what you might do to make it better. Spring is upon us, trees and shrubs are waking up in my garden, but perennials are still mostly dormant and woody plants are just beginning to leaf out. It is a good time to look at “the bones” of the garden and decide what needs to be done.

The bones of the garden are the trees, shrubs, stone walls, sculpture, water features and pathways. These are visible in winter, though often covered in snow. In summer they can become focal points, or almost disappear as flowering plants shout out for attention.

Each of us reacts to spaces a little differently. Some want an enclosed garden that is quiet and private. Others want a long view of the sea, a pond or a distant mountain. If you are lucky, you might be able to divide your garden up so that you enjoy more than one type of garden: sunny, shaded, private or open to the view of passers-by. If you have just a city lot, you may have to choose just one kind of garden to focus on.

Making a garden private means creating visual barriers. You can do that overnight by hiring a company to put up a wooden 8-foot fence. Your neighbors may not like this and walls are generally monochromatic and boring. Of course you can then grow vines up them, or plant trees and shrubs in front of them, but plants take time to fill in and disguise the fence or wall. Still, if you have a new puppy or a bouncy 4-year-old child, you may opt for the immediate enclosure provided by fencing.

Alternatively, you can plant trees. There are advantages to this: trees get bigger and better every year. They provide habitat and food for birds, pollinators and all sorts of small animals. They reduce water runoff. And although some require occasional pruning, most of Mother Nature’s trees do just fine on their own. Some are fast growing; others will just inch along, holding place without shading the understory.

The street side of your house is important. What you show the world says something about you. If you plant a tall hedge, it can send a signal to others that you wish to remain undisturbed. If you have just lawn, it says you are not a gardener. If you plant beds and islands of color, you are saying, “Welcome, and enjoy!” Of course, lawns are the easiest to maintain, especially if you accept my mantra, “If it’s green and you can mow it, it’s a lawn.” I love a few dandelions and love my clover, which fixes atmospheric nitrogen into the soil — it’s free fertilizer.

Trees and shrubs are important on the front lawn as much as in the gardens behind the house. You can break up the straight lines of driveway and front walk. When thinking through your plans, take a garden hose and curve it around to define spaces. Create beds with bump-outs, and drive stakes to indicate where you might add trees, and use shorter stakes to indicate shrubs. And instead of lawn between the trees, imagine groundcovers. It will soften the look of your home, and invite birds and pollinators. You can keep some lawn, just reduce its footprint.

What other bones can you add to your property? Stone is wonderful in all its forms. The simplest stone additions are just boulders or tall, narrow standing stones. One and done. Stone walls are delightful, but expensive.

You can also build a cairn — a pile of stones similar to the markers seen on mountain trails above the tree line. The key, if piling up stones to create a pyramid or cairn, is to ensure that each stone is resting on two stones below it. And be careful that when you touch a stone it does not tumble. The earth does move a bit with the seasons, so building a sturdy structure is important.

Water features are nice, too. A simple bird bath can add interest and provide water for insects and birds. I have a blue ceramic birdbath that adds color and height to a flower bed — even though the birds seem to ignore it. I was told to put a stone in the water for them to perch on, but even that has not lured them in. Of course, I have a brook nearby, so that is probably their choice instead.

Pathways are important to gardens. They can keep your shoes out of mud and protect the soil from erosion. Flat stones are great, as are pea stone and small gravel. Chipped branches or bark mulch can be used for walkways, too. Pathways naturally lead one forward to other parts of the garden. Grassy paths are simple, and work well so long as they are not worn bare by too much foot traffic.

So go outside and do some planning — even if it is too early to take much action now.

Henry is a garden designer living in Cornish Flat, N.H. He is the author of four gardening books. His website is Gardening-Guy.com. Reach him at [email protected].

Featured photo: A simple blue birdbath can add color and interest. Photo courtesy of Henry Homeyer.

How growing native trees and shrubs can help

By now birds are finding their own food and have less need for that sunflower seed we have been providing during the cold days of winter. Now, growing native trees and shrubs on our property can be a huge help to our bird friends.

It is not enough to put out birdhouses; we need to help birds find food for their chicks. The diet of baby birds is about 90 percent composed of caterpillars, which are high in the fat and protein that developing birds need to grow and be healthy. One clutch of chickadees can, according to entomologist Doug Tallamy, a Ph.D. researcher from the University of Delaware, consume 6,000 to 9,000 caterpillars in the 16 days from hatching to fledging. And most parent birds continue to feed their chicks even after they have fledged.

In Tallamy’s new book, Nature’s Best Hope: A New Approach to Conservation That Starts in Your Yard, he explains that not all trees and shrubs are created equal. Those that evolved alongside the butterflies and moths are palatable to them. Those that were imported from Asia or Europe mostly are not of interest to them.

Most woody plants create toxins or bad-tasting chemicals to keep all sorts of animals from eating them, but caterpillars have developed ways to eat most native tree leaves — they have adapted to eat what was available to them.

Although caterpillars eat the leaves of our native plants, they rarely damage or defoliate their host plants. Tent caterpillars and a few other imported species will defoliate trees, but that’s rare. It’s just that most of us never notice the little holes chewed in the leaves that are supporting the caterpillars. In fact, I rarely notice caterpillars in the trees and shrubs at all, but our bird friends certainly do. They evolved along with the caterpillars and are genetically programmed to recognize them and bring them to their young, even birds that are seed eaters.

As Dr. Tallamy explains in the book, not all native plants are created equal. Some native species may only feed a few. Some, like our oaks, feed many hundreds of species of caterpillars. These “keystone species” are critical to supporting our wildlife. Five percent of the native species support over 70 percent of our lepidoptera, according to Tallamy.

So what plants are best to feed the caterpillars that support our birds?

According to Tallamy’s research, native oaks, cherries, willows, birches, poplars and elms are best, and goldenrods, asters and perennial sunflowers “lead the herbaceous pack.” The National Wildlife Federation’s Plant Finder website (nwf.org/NativePlantFinder) allows you to enter your zip code and see what plants are best for your zone, and how many pollinators are served by each.

Tallamy did a study in Portland, Oregon, and found that of 1,176 trees he identified on the streets there, 91.5 percent were from other continents or ecoregions, mainly Asia. What does that mean? Portland is a pretty city with lots of trees, but it is largely a wasteland for caterpillars that feed our baby birds. The birds need to nest where they can get food for their young.

If you wish to improve your landscape and plant native species that will support wildlife, think about reducing lawn size. Tallamy explains that there are 40 million acres of lawn in America, an area the size of New England. Thirty percent of our water is used to water lawns, and 40 to 60 percent of all fertilizer ends up in our waterways and drinking water, he wrote.

Doug Tallamy proposes that we all join him in creating a “Homegrown National Park” by reducing our lawns by 50 percent and growing native plants. This will create wildlife corridors and improve our environment in many ways. The plants will sequester carbon in ways that lawn does not. It will help to save endangered species of insects and birds. It will reduce pollution of our air and water.

According to one study, in newer housing developments lawn covers about 92 percent of space not covered with driveways and buildings. If we were all willing to reduce our lawns and add trees, shrubs and native perennials, that would make a big difference in helping to reduce species extinction of lepidoptera, birds and small mammals. It does not require eliminating lawn, just reducing it. Think of lawn as area rugs, not wall-to-wall carpeting.

What else can you do to help our birds? Add a water feature. Even a small pool with a recirculating pump will attract birds, especially migrating birds that need sustenance for their long journey.

Instead of lawn, add native groundcovers. Lawns get compacted by lawnmowers, making it difficult for caterpillars and native bees to burrow in the ground. Most caterpillars pupate in the ground or in leaf litter, but lawns are not suitable. Other than honeybees, most bees burrow into the ground or into decaying wood to lay their eggs and hatch their young.

You can go to homegrownnationalpark.org to register your property as part of this movement.

Featured photo: Bird houses are nice, but we need to do more for our baby birds, including growing native plants. Photo courtesy of Henry Homeyer.

Frost, soil, drainage and other considerations

I know some gardeners who plant their potatoes or tomatoes in the garden on the same day every year. Not me. I think planting time is best based not only on the last frost date in your garden, but also on the soil temperature and up-to-date weather predictions. And of course late frosts do occur unexpectedly and can wipe out your tomato or pepper seedlings. So don’t jump the gun.

The internet has many guides and suggestions for when you should plant, but I think an experienced next-door neighbor probably has a better sense of when to plant. So, for example, one internet source says the last frost for Cornish Flat is May 15, while another internet source says June 11 to June 20. That’s over a month of difference!

My vegetable garden is in a low spot, with hills on either side. Cold air slides downhill, so I am cautious about planting too early. Often there is a late frost in my garden, but not around my house, which is 15 or 20 feet uphill. Rivers, lakes and the ocean can have a warming effect, too. The closer you are to the Connecticut River or the Atlantic Ocean, the sooner you can plant.

It is often thought that a full moon will cause late frosts. But a friend of mine used the frost data his mother had collected over decades and compared it to the phases of the moon. He observed that the moon does not seem to affect frost dates.

Soil temperature is important, too. Seeds are genetically programmed not to germinate if the soil is too cold. That makes sense: Seedlings are tender and many can be damaged by frost. So you can plant spinach or pea seeds “as early as you can work the soil,” according to the package, but they may not germinate for weeks if the soil is cold — and they may rot.

Seeds can rot in cold, wet soil. Corn seeds are particularly susceptible to rot, and many are treated with fungicides to prevent rotting. But as organic gardeners, we should avoid treated seeds.

If you are in a hurry, you can warm up the soil. First, rake off any fall leaves or other mulch from your garden beds. That will allow the sun to warm the soil, and air to evaporate some of the melted snow and spring rains that make the soil soggy.

Raised beds help with drainage. My vegetable garden is near a stream and the water table is high, especially in spring, when it is occasionally flooded. Each fall I shape my beds for spring, raking soil into the beds before covering them with leaves. In the spring I rake the leaves into the walkways, but after the soil has warmed up in mid-June I will put down hay and newspapers around my plants.

If you want to warm the soil and kill any annual weeds that start growing early in the season, you can cover the soil with clear plastic. If you get what is called “4-mil” plastic, you can reuse it. Flimsy stuff sold to painters is not usually reusable. Be sure to pin down the edges, or better yet, put soil or boards over the edges to keep wind from lifting the plastic and cooling the soil.

On a sunny day the temperature under the plastic can exceed 100 degrees, “solarizing” weeds and killing them. Perennial weeds and grasses will have their tops browned, but it will not kill the roots unless you do this for a long time.

So what seeds can you plant early? Spinach, peas, lettuce can be planted 3 to 6 weeks before last frost. In the fall I let a few lettuce plants flower and go to seed. Those seeds fall on the soil and start up much earlier than I plant any lettuce. But I also start lettuce indoors to get nice-sized plants in the ground in May for early eating. Carrots, beets, onion sets and radishes can go in the ground a week or two before last frost.

Tomato, pepper and squash family seedlings I plant in mid-June, well after last frost because I want the soil to reach at least 60 degrees before planting. Because I am bothered by a beetle that eats my cukes and squash I start those indoors instead of by seed outdoors. When the vines are about 6 inches long I plant them outdoors. By then they will survive any beetle munching.

Before planting any seedling outdoors, be sure to harden off the plants. That means to start putting the seedlings outdoors a few hours a day and increasing their exposure over the period of a week or so. You should do this for store-bought seedlings, too, as they have probably been protected from sunburn and windburn inside a greenhouse. But ask at the nursery if they are hardened off.

You can protect seedlings from light frost by covering them with something called row cover, Reemay, or Agribon. These are spun agricultural fabrics that come in 5-foot-wide swaths that you can cut to fit your rows. Unlike plastic sheeting, this stuff breathes and allows moisture to pass through it. Buy the wires sold to support it and form hoops over your plants. It will also keep bugs off your plants, but you need to remove it when vine crops start to bloom — they are insect pollinated.

The more you garden, the more you know. But we never know exactly when a late killing frost will come. So I am always the last on the block to get my garden planted — but my plants catch up.

Featured photo: Row cover with hoops helps to keep insects off and keep plants warm. Photo by Henry Homeyer.

How to create early spring arrangements

I miss being able to go to my garden and pick flowers for the table. Yes, spring is on the way and even feels present on good days now. But it will be a while until my daffodils and tulips bloom. My winter aconite, small yellow bulb flowers, are blooming, and little white snowdrops have pushed through frozen earth. Those mini-flowers aren’t really suitable for a bouquet, but I’ve picked a few things that please me.

First, I picked some stems from my Merrill magnolia. It is loaded with fuzzy buds for its late-April blooming, and these look good in an arrangement. Magnolia branches tend to fork and grow in different directions, so placing stems in a vase can be tricky. I put some in a dry vase with dried flowers and seed-bearing stems and one in a vase with water to put on a windowsill. The buds I picked on Jan. 31 bloomed on March 17.

Beech branches are good for arrangements, too. The young trees, anyway, hold onto their light brown leaves, filling spaces in a vase. And the stems are a smooth gray, with cigar-shaped, pointy buds.

Of course red- or yellow-twigged dogwood stems add color to a winter arrangement. Each year one must cut back the plants in spring or winter to get the color on the new stems. They are fast-growing plants, so they can grow 5 feet of new stem in a single summer. They grow best in moist or marshy places.

For contrast in my vase I like to have some dark stems. Trees in the cherry family do well there. Chokecherry, pin cherry and black cherry look good in a vase. Young white birch have dark stems, as does hop hornbeam. But basically you can pick any tree branches if you like their look.

Greenery is nice for contrast with bare stems. I recommend white pine for greenery. It has a nice weeping tendency and is great around the outside of the vase. Unlike Canadian hemlock, it holds onto its needles quite well, but hemlocks are more common on my property, so I often use them.

Then there are the hydrangeas. Many species and varieties hold onto their flower panicles well into winter and can be quite nice in a vase. My favorite is one called Pink Diamond. It has long stems and it holds onto the fertile and infertile inflorescences, showing contrast between white and black florets on the panicles. Although the blossoms are pink toward the end of their bloom cycle, they are not pink after frost.

Winter weeds can be interesting, too. One of my favorites for winter picking is teasel. Technically, this is a biennial weed. I harvested some seeds from a corn field in Ohio years ago. The corn farmer thought I was a total nutcase because to him teasel is a noxious weed. But I have learned its habits and allow just half a dozen plants to flower and produce seed every year, and it is a delightful addition to winter arrangements.

The key to keeping teasel in check is to recognize the first-year plants. They are rosettes of light green leaves. I pull most, but leave half a dozen to mature and bloom in Year 2. The second year plants are loaded with thorns and have a deep tap root, so if you pull them then, you must wear gloves. I rub the thorns off while wearing gloves as I pick them, and can then handle them with ease when arranging them in a vase.

Astilbes bloom magnificently for me, and their winter stems are great in a dry vase. I have many different species and varieties ranging from short (12-inch blossom stems) to tall (48 inches). Their chief requirement is moist soil, and I have plenty of that. If you don’t have moist soil, the leaves will brown up in the heat of summer. One trick I have tried in dry locations is to bury a plastic bag a foot or so deep in the soil before planting. That will act like a little bathtub and hold some water in dry times. They like a half day of sunshine, and prefer morning sun.

Snake root or black cohosh (formerly called Cimicifugaspp. Now in the genus Actea) holds on to dry blossoms long after summer has passed. They look good in dry arrangements if you have any still standing.

Winter arrangements tend to be fairly monochromatic — tan or brown colors are most common. I have seen gardeners use dry allium (onion-family) blossoms to bring color to the table by spray-painting them with red, blue, purple and yellow spray paints. I have never done so, but if I think to harvest some next spring or summer, I may do so. I have even seen them sprayed while still in the garden!

Of course, the best color in the house for me right now is my forced daffodils. Last fall I potted up plenty of “tete-a-tete” daffodils and I kept them in my cold cellar until recently. Each bulb provided many blossoms and even now, after the flowers have gone by, they are still pleasant-looking with green leaves and dried yellow flowers.

Featured photo: Winter aconite. Courtesy photo.

Your fruit trees are ready for a haircut

When I was a boy I loved to climb trees. I had no fear of heights, and loved the unique perspective I got looking down from the top of a tall pine or maple tree. Now that I’m all grown up, I no longer climb trees — unless I have the excuse of pruning, which I also love. On a recent warm, sunny day I got out my pruning tools and ladders to give my fruit trees “haircuts.”

A word about timing: Conventional wisdom has it that you must prune apples and other fruit trees in March. Hogwash. You can prune them any time. I generally stop pruning when flower buds start to open, but prune again in August and in late fall after leaf drop.

Good tools are important for doing a good job. You need sharp bypass pruners (not the anvil pruners that crush the stems), a pair of good loppers and a small hand saw — folding saws with sharp teeth are good. I have bigger saws for large branches and even a small electric chain saw, but rarely use them.

Start by walking around the tree a few times and really looking at the structure of the tree. I want my trees to have enough open space that sunlight can get to every leaf. Sunshine feeds the tree and dries out leaves, helping to minimize fungal diseases. A robin should be able to fly right through a mature apple tree without getting hurt.

My first cuts are usually the biggest branches that need to be removed. It’s easier to remove one 3-inch-thick branch than snip away 50 small branches on it. If you prune every year, you may not have a big branch to remove, but it’s surprising how quickly water sprouts turn into big branches going straight up through the middle of the tree. You can often reduce the height of a tree by shortening big branches.

Water sprouts grow every year on most fruit trees. The first year they are pencil-thin and 12 to 36 inches long. Cut them off as they will just clutter up your tree. Trees grow them in response to a need for more food for the roots, and they are most common in shady parts of the tree where leaves are not getting enough sunshine. Some varieties are more prone to growing water sprouts than others, and a hard pruning may stimulate them to grow in large numbers.

Dead wood should always be removed. In winter there are no leaves on the tree, and it can be tougher to determine what is dead. Look for dry, flaking bark. But the sure test is to take your thumbnail and scratch off a layer of bark. If you see green, it is alive. If not? It’s dead.

Look for rubbing branches, or branches so close that they will grow together. Choose one, and cut it off. Some trees, maples, for example, often send up branches that originate at the same point and are growing in the same direction. Remove one before they grow together and fuse (which results in a weak spot subject to breakage). Maples and birches, by the way, should not be pruned now when the sap is flowing fast. Do them in the fall, or even mid-summer.

Branches often grow away from the center of the tree, as they should, but compete with another branch directly above or below it. Decide which is the better branch, and remove the other. I also look for branches that are headed into the interior of the tree and remove them.

When pruning, don’t leave stubs. Cut back each branch to its point of origin: the trunk, or a bigger branch. This will promote healing.

Fruit spurs on apples and pears produce flowers and leaves, and are indicators where you will have fruit later this year. They are easy to identify: they are short gnarly branches (3 to 6 inches) that have fruit buds. Fruit buds are bigger and fatter than leaf buds. They do not generally appear on young fruit trees. Learn to recognize them: when deciding which of two branches to remove, keep the one with more fruit spurs.

Fruit most often develops on what are called scaffold branches — sturdy branches that leave the trunk on an angle that is almost parallel to the ground, or aiming up slightly. Branches that go more straight up, older water sprouts for example, produce little or no fruit.

You can change the angle of growth of a branch that is only an inch or less thick. Once winter is over, attach string or rope to a branch and tie it to a peg in the ground or to a weight to bend it down. A half-gallon milk jug works well. Just add water until you have the correct angle on the branch. Forty-five to 60 degrees off vertical is fine. You can remove the weights in June.

When pruning, don’t overdo it. Trees need their leaves to feed the roots and fruit. In any given year don’t take more than 25 percent of the leaves (woody stems don’t count when calculating how much you have taken off).

One last fact: A well-pruned tree will produce fruit that is bigger, sweeter and tastier than a tree that has been neglected. I don’t want lots of little fruit, and I try to remove some each year in June to encourage fruits to grow to full size. Leaves that get plenty of sunshine will produce more sugars for the fruit, so it will taste better. So get to work!

Featured photo: Fruit spurs are short with a fat bud or two. Courtesy photo.