How is your soil and how can you improve it?

Dig some holes, see what you’ve got

Most gardeners know that success in the garden depends on many factors: You can’t grow a sun-loving plant in a shady area, for example. And a shrub that loves wet places won’t do well in dry soil. But the key to success is really the quality of your soil. Not only that, any soil can be improved with some help from you, the gardener.

Ten thousand years ago the glaciers made a final pass over New England, grinding rocks into sand and smaller bits that became sandy, clay and loam soils. Soil is made up of roughly 45 percent ground rocks, 5 percent organic matter, and the other 50 percent is air. Surprisingly, plants get their oxygen through their roots, not leaves.

Of course if you have been driving your car over the lawn, it is compacted and has much less air. Even walking regularly over the ground will compact the soil, which you should avoid, especially when the soil is wet. Compacted soil not only has less oxygen, but also is tough for roots to penetrate, and it is more likely to be waterlogged. Crabgrass does much better than planted grasses in compacted soil.

An easy test for soil compaction in your lawn is to take a screwdriver with a 6-inch shaft and see if you can easily insert it into your soil. If not, the soil is seriously compacted. A lawn with compacted soil will improve if you spread a half-inch layer of compost over it every year. Earthworms and other soil organisms will slowly move it into the soil, improving it. Flower and vegetable beds can be loosened with a fork or hand tool.

It makes sense to get a soil test done every three years to see if your soil is improving with your efforts. Your state extension service has a lab that will test your soil for a fee. Get the home garden test, which will tell your soil pH (acidity), mineral content, organic matter content and soil texture. If your vegetable garden is near the house and it was built before 1978, get the soil tested for lead (the law prohibiting lead in paints passed in 1978). Some states include testing for lead for free in the standard test.

By adding compost or aged manure to your soil in the garden, you will increase the percentage of organic matter and improve soil texture or tilth. You should have at least 4 percent organic matter, and 8 percent is terrific. I add compost every time I plant anything, even though my soil is excellent. Good compost contains lots of living bacteria and fungi that help plants.

Your soil test will not tell you how much nitrogen your soil has, as that number varies daily according to moisture levels and temperature. But if you have plenty of organic matter, it probably has adequate nitrogen. Still, I add some slow-release organic fertilizer when planting anything except annual flowers. Organic fertilizer (unlike most chemical fertilizers) provides nitrogen and other nutrients slowly, rather than all at once. This encourages healthy growth, not a fast spurt of green growth.

Two simple tests you can do involve digging holes. Dig a hole with straight edges down at least a foot to see the soil profile. The top layer will be darkest, as that is where the topsoil is — maybe just 2 inches, or maybe as much as 6 inches. The deeper the topsoil, the better. Adding compost and working it in will increase the quality of the soil; the top 6 inches of soil is where most plant roots are (except for trees).

The next layer is subsoil, which is a different color, perhaps a light brown or reddish brown. Finally, you may get to a layer of sand, gravel or clay. Sand or gravel will help your soil drain well; clay will act like a barrier, holding water. If the soil stays wet much of the year, it will be gray.

Drainage is important for most plants. You can test this by digging a hole 24 inches wide and about 8 inches deep. Fill it with water. If it drains out right away, or within 20 minutes, you have very good drainage. If it holds water for a few hours, especially if there has been much recent rain, you are fine. If it holds water overnight, you have a drainage problem.

If you have a drainage problem, you can build raised beds, either with wood sides or just mounded up. There are plenty of companies selling raised beds or corners for making raised beds with lumber you buy locally. Most lumber stores will cut your lumber to length.

Another simple soil test you can do for free is to moisten some soil, then rub it between your fingers. If it is sticky, it is a clay soil. If you feel grains of sand, it is a sandy soil. If it is neither, and is a nice brown color, you have a good loam, which is what you want.

The last test is to take a handful of moist soil and try to form it into a cylinder. Clay soil will hold together well. Loam, which has some clay, will hold together but break apart if you touch it with your other hand. Sandy soil will fall apart when you squeeze it. The remedy for sandy or clay soil is a generous dose of compost.

Rome was not built in a day, the saying goes. This is true for soil, too. It takes years to get your garden soil in optimum condition everywhere. So work on the places where you are planting for quicker results.

Featured photo: Raised beds are great for areas that flood or stay wet. Photo by Henry Homeyer.

No Mow May

An idea for more pollination and less pollution

In 2019 a British nonprofit called Plantlife coined the term “No Mow May.” They proposed that gardeners leave their mowers in storage for the month of May in order to let wildflowers and weeds bloom and provide pollen and nectar for pollinators. And of course the caterpillars of many pollinators feed all our baby birds, so the ramifications are vast.

Early spring is a tough time for pollinators, especially here in New England as there are not many flowers to visit. I like the idea of a simple action that can have positive effects on so many species of wildlife.

The most obvious advantage to you is that you have a few extra hours to do other things in your garden. Next, you are not spending any money on gas or electricity. Most gas-powered mowers do not have the emission controls that are required for cars. According to the Environmental Protection Agency (EPA), one hour operating a new gasoline lawn mower emits the same amount of volatile organic compounds and nitrogen oxide as driving a new car 45 miles.

According to the EPA, lawn mowers and other garden machines like leaf blowers, string trimmers, etc., contribute as much pollution as our cars and homes. The statistics on lawns are deceiving; two percent of the land mass in America is lawn. But that is more square miles of land than all the corn grown here. Roughly 80 percent of homes have at least some lawn.

If we mow our lawns from May to the end of October, that’s six months of mowing. Eliminating one month of mowing reduces those emissions by 17 percent. Good for the environment, good for the wallet.

For the last two years I have been installing trees in what was a 5-acre lawn in Hanover, N.H. So far we have planted about 150 of them — and we largely stopped the mowing, just leaving pathways throughout. The owners now have their field mowed everywhere just once every two years to control growth of unwanted woody plants like poplars, which spread by root.

We were delighted last spring to see the field come alive in spring. At least a dozen species of flowers bloomed, probably more. And the bees and other pollinators just loved it.

What happened when we just stopped mowing? Grass grew, and largely flopped over as it got taller. It was nothing like the unruly 2- or 3-foot-tall mess that the mowing guys predicted. We were always able to walk anywhere in the field even though it was not mowed. Of course, when the mowing crew shows up soon, they have big, industrial-scale mowers that will chew up anything.

For your home lawn you may want to pay attention to how tall the grass gets in May. Presumably your push mower or electric mower will not mow tall grasses as easily as the riding mowers used on the field described above. If you can only avoid mowing for two or three weeks, it’s still better than mowing it short every week in May.

Another advantage to No Mow May is that you will probably end up with a better, more resilient lawn in times of drought. The longer your grass, the more food it produces for the roots, allowing them to grow longer and deeper.

Your lawn might complain about being mowed short on June 1. So put the blades up as high as they go. The lower parts of blades of grass may be a little pale in color as they were shaded out by the taller parts. Leave your lawn a little longer this year — it doesn’t have to look like the infield of Fenway Park.

What about bare spots on the lawn? These are often filled in with crabgrass, an annual weed. For large areas, you will need to plant new lawn seed — the sooner the better. Filling in empty spots can be done in May by scratching the soil with a short-tined rake to loosen the surface. Add half an inch of compost and mix it in with the soil. Then spread seed over it — just broadcast it with your hand in small areas. I use a lawn/leaf rake to mix the seed in with the soil: I flip over the rake and drag it lightly over the area, which mixes in the seed well. If you have a metal tamper, use it to press down the planted area. If not, use a small board and step on it.

I never fertilize my lawn, and it looks fine to me. If your lawn is a little feeble, check the soil pH. If it is too acidic, you can spread some limestone. Lawn grass prefers nearly neutral pH.

So take a break from mowing this May.

Featured photo: Drumstick primroses. Photo by Henry Homeyer.

Early spring bloomers

Look at all the pretty flowers!

I like to have blossoms in the garden and in vases everywhere. I try to have something blooming all the time, or as often as possible. Right now, in mid-April, I count more than 10 species of plants in bloom, along with seven species of bulb plants that are blooming by the hundred for me.

Let’s start with trees and shrubs — what I call woodies. The most unusual woody is leatherwood (Dirca palustris). This is a native woodland plant that does well in part shade. Although the literature says it prefers moist, rich soil, I have it in dry soil and it does well there.

Leatherwood has small greenish-yellow flowers that appear about the same time as forsythia — mid-April for me. Mine is slow-growing with lovely gray bark that reminds me of beeches. This is a well-mannered plant that stays 3 to 6 feet tall and wide.

February Daphne (Daphne mezereum) is in bloom now with highly fragrant pinky-purple flowers. It is originally from Europe, Turkey and Iran. I love it so much I named a corgi after it (she is now gone, alas). It stays 3 to 5 feet tall and wide. In the fall it produces small red berries.

Magnolias are in bloom now, too. My favorite is the Merrill magnolia, a hybrid that produces double white lightly fragrant flowers. I planted mine as a small tree in 2004, and now, 19 years later, it is about 40 feet tall with a spread of 25 feet. It blooms reliably (nine years out of 10) on my birthday, April 23. It is a good specimen tree to put in a lawn and will do well even if the soil is consistently moist to soggy.

Forsythias are in bloom everywhere with bright yellow flowers. If yours only blooms down low, in the area covered by snow, the buds that were formed last summer were killed by the winter cold. So get rid of it and buy a new variety such as New Hampshire Gold, Vermont Gold or Meadowlark. All are hardy throughout New England.

My favorite early spring perennial is called the drumstick primrose (Primula denticulata). It comes with flowers in purple, blue, pink, magenta and white. The florets are small and arranged in 2- to 3-inch globes on 6-inch stems. They do best in moist to wet soil in sun or partial shade.

Hellebores or Lenten Roses (Helleborus orientalis) are also wonderful spring flowers. Mine have been blooming for a couple of weeks already and will continue on for another month or so. The blossoms are five-petaled and 2 to 3 inches wide with yellow stamens in the center. Colors range from white and cream to pink, purple and nearly black. They are evergreen, but last year’s leaves should be cut off now as they are all bedraggled.

A dainty flower with beautiful finely cut foliage is a spring ephemeral called corydalis or fumewort (Corydalis solida). It pops up in my garden where it wishes, and I am always glad to welcome it. It seems to do best in moist, part shade with rich soil. The flowers on mine are small, long-spurred light blue, but other colors are also possible. There is a yellow variety of a related species (C. lutea).

Lungwort or pulmonaria (Pulmonaria spp.) is a good ground cover that is blooming for me now, too. It is interesting that a single stem might support blue, pink or apricot flowers all at once. All do well in shade or partial shade and better in moist soils than dry soils. It spreads by root.

There are at least a dozen different species of pulmonaria including P. longifolia with spotted leaves and multicolored blossoms. The one I like best is P. angustifolia, which has very intense blue flowers and solid green leaves. I’ve read that varieties or species with more white spots grow better in full sun than those with fewer or no spots.

Wildflowers are starting to bloom, including one of my favorites, bloodroot (Sanguinaria canadensis). These white multi-petaled flowers come up from the soil wrapped in the leaves that look like a green cigar. On cold days, or at night, the blossoms close up, but they open on sunny days when the bumblebees are working.

The bloom season of bloodroot is short, but there is double bloodroot which is sterile and blooms for a longer time. Like all bloodroots, the clumps get bigger every year, so you can dig them up and divide them to start doubles in new places. The sap from the roots is poisonous, so wear gloves when dividing any bloodroots. Do that now or in the fall.

We certainly deserve spring blossoms for having survived winter and mud season. But you do have to plan and plant for those early bloomers.

Henry is the author of four gardening books and is a 25-year veteran of the Master Gardener program. Reach him by email at [email protected].

Featured photo: Drumstick primroses. Photo by Henry Homeyer.

Things to try — or not!

One option: grow a lot of something you love

Are you in a rut? Spring is here, but most of us cannot plant anything outdoors due to cold nights or wet ground. Yes, you can plant seeds indoors and baby them until early summer, but that requires a place to grow them and lights to keep them happy. So maybe you should put on your thinking cap and decide what you want to do later on, and do some research.

For starters, you could join a plant society, of which there are many. If you love daylilies, join the American Hemerocallis Society. You will find people who love daylilies, too, but have much more knowledge than you ever will. You will learn how to collect seeds and to hybridize daylilies of new colors.

Or what about the International Aroid Society? The Arum genus has a diverse collection of plants from skunk cabbage to philodendrons to Colocasia yams. The Plumeria Society of America is focused solely on the 11 species of plumeria, known as frangipani in English. Hostas? Wildflowers? Boxwood or bonsai? There are societies for each and every group.

An easy project indoors would be to start an avocado tree. Avocados ripen in California starting in spring and going through summer. Winter avocados won’t usually sprout from their seeds — they have been in cold storage too long. The classic method is to perch a seed in a glass of water using three toothpicks to keep its bottom just kissing the water. Put the point end up and the fat end down. I cut one open recently, and it was already sprouting! So I planted it in a mixture of potting soil and compost. I let the sprout just peek out above the soil line.

I have grown many avocado trees over the years, generally by recognizing the shiny leaves in my compost pile. So I know that you don’t have to suspend the seed in water — they will be glad to grow in compost. When I lived in West Africa I was able to buy avocados for a penny or two apiece, and often fed them to our cats. Cats love them because of their oil content. I have a 5-foot-tall avocado tree growing in a 12-inch pot that lives as a house plant in winter and goes out on the deck in summer. It started life in the compost pile.

Try to remember the favorite flowers of your grandparents, or your parents. This would be a good time to ask your mom, for example, what did her mom really love? My grandmother, who died in 1953, loved peonies. My mother, may she rest in peace, dug up one of her mom’s peonies and moved it from Spencer, Mass., to Woodbridge, Connecticut, and grew it for decades before I came along and divided it in the early 1980s and brought a part of it to Cornish Flat, where I live. The peony I got is ‘Festiva Maxima,’ a highly fragrant double white with splotches of red inside — blood from a fairy princess, I think.

If your Grammy loved roses, study your yard and figure out where one could go in loving memory of her. And do a little research now if you have never grown roses. Roses are easier to grow now than they were 40 or 50 years ago when Grammy was growing them. I love the ‘Knockout” series of roses. The Knockouts are not fragrant, so they do not attract Japanese beetles, and they bloom for months.

Think about planting an oak later in the month. Many gardeners don’t think of planting oaks, saying they get too big or grow too slowly. But it has been proven that oaks are the No. 1 best plant to support our birds, pollinators and mammals. And you can even plant a sprouting acorn now.

Oaks probably grow faster than you think. I planted several bare-root oaks in the spring of 2021. They were as thick as a pencil and only a foot or two tall. In two years many of them have taken off and are 3 feet tall or more, and they will be 10 feet tall in less than five years.

Want a fast-growing flowering tree? Plant a catalpa. They are native and the flowers are amazing. Fragrant, attractive. The leaves are huge — big enough that Native Americans used them for diapers for babies, I’ve read. I bought a 10-footer five years ago and now it is already a shade tree — 25 feet tall with a 20-foot-wide crown.

What else can you do? Grow a lot of something you love, starting from seed. I love rosemary, and recently bought a packet of seeds and planted 50 seeds. If all goes well, I will have plenty to share.

I will grow them on an electric heat mat (designed for use with seeds) as they germinate best at temperatures in the 70s. Once they have germinated I will grow them under very bright LED lights and will transplant them into rows in my vegetable garden in mid-June. Of course I will keep some in pots, and grow them on the deck.

Lastly, plan on growing a vegetable you have never grown before. You might try tiny decorative pumpkins, or huge ones. Or rutabagas. Dreaming big is part of being a gardener.

Featured photo: Oaks are pretty for us and food for caterpillars and wildlife. Photo by Henry Homeyer.

Henry is a UNH Master Gardener and the author of four gardening books. His website is Gardening-Guy.com. Reach him by email at [email protected].

More chores for spring

Walk gently and carry a soft rake

Although I still have some snow around the house here in Cornish, New Hampshire, many of you may be looking at brown grass and mud. It will be some time before real spring weather is safely ensconced. We all want to get outside and enjoy warm, sunny days, and most of us are itching to do some work in the garden.

If you do go outside, please be extra careful where you walk. Your lawn and gardens are probably soggy, and your footsteps can easily compact the soil and damage roots. Take a different route to your garden each time you go out. Game trails in the forest can be made by animals as small as a housecat due to compaction if they follow the same path, day after day. Plants do not thrive if their roots are in compacted soil.

I live on a dirt road, and each year the town plows dump sand and gravel mixed with snow on the lawn. I try to shovel that grit and snow back onto the road or haul it away while it is still mixed in with snow to cut down on raking later in spring. Use a soft rake, one with bamboo or plastic tines, when you rake the lawn so you will be less likely to tear up the grass as you rake.

If you have decorative grasses that overwintered, they are probably pretty bedraggled by now. It is better to cut down tall grasses before they start growing. Last year’s stems will not turn green- they grow new stems each year. The only problem you might have now is that they may be in a garden bed that you wish to avoid walking in. I use a serrated knife for the job, but pruners will work, too.

If you want to work in flower beds, find a couple of 3-foot-long 6- to 8-inch-wide planks. Place them in your garden bed and step on them instead of the soil. They will distribute your weight and allow you to work while avoiding the problem of compacting the soil.

If you have bluebird boxes or other nesting boxes, this is a good time to clean them out. I don’t know just when the bluebirds arrive and claim their nesting places, but I want to be ready for them. This would also be a good time to put up a bat house. Bats eat lots of mosquitoes, so you should welcome them to your garden. Pre-made bat boxes are available, and directions to make your own are available online.

I love art and whimsy in my garden, and I have all kinds of interesting art placed around my property. I recently noticed that some of it has tipped or fallen over. Depending on the nature of the whimsy, you might be able to right it now. Others, such as wire sculpture that has rods designed to go into the soil, might have to wait. My soil is still frozen, which deterred me from fixing all of mine that needed straightening.

It’s too early here for me to rake leaves and clean up garden beds that need it. But I am picking up sticks that were blown out of trees. After a little drying time in the barn they will provide me with kindling for my woodstove.

In the past I piled up broken branches each year and burned it all in late winter while there was still plenty of snow around the pile. I have stopped creating burn piles, for two reasons. First, little animals may have settled into the burn pile over the winter, and I don’t want to evict them or possibly kill them. And certainly there are lots of insects that overwinter in dead branches and stems of things like goldenrod and bee balm, which used to go into the burn pile (but are now composted).

The second reason is environmental: The bonfires I enjoyed in the past send up a lot of smoke and air pollution, and I want to avoid doing that. Instead of burning those branches, we bought a chipper/shredder to make chipped branches that can be used on pathways to keep down weeds. Or they can be double-ground and the fine results are good for mulching or mixing with food waste in our compost pile.

Chipper shredders come in many sizes. We bought a gasoline-powered machine that will allegedly take 3-inch stems but is actually better for things half that size and smaller. Manufacturers want to sell their products, so they tend to exaggerate a bit. But buy the most powerful machine you can afford. Ours cost $600 and is good for our needs.

What don’t they tell you? Chipper/shredders are noisy and can be dangerous. Mine does not start in winter. One pass though the machine makes a rough mixture of shredded branches that is not aesthetically pleasing to my eye as a mulch. But this material is easily dumped in the top hopper for fine grinding. Electric machines are out there, but the ones I’ve tried are not as powerful as a gas-powered machine. Good for small branches and leaves, I suppose.

I’ll start my tomato seedlings around April 10 indoors. These I will plant outdoors around June 10. Vine crops I’ll plant later — early May will be fine for cukes, squash and pumpkins that will go out in mid-June. I don’t need to tend seedlings any longer than need be.

Spring and summer are just around the corner. So try to be patient and avoid compacting your soil. If you see footprints in the soil, you should stay off it. Or wear your snowshoes to get around the garden!

Featured photo: This plank will let me cut down this decorative grass without compacting the soil. Photo by Henry Homeyer.

Henry is a UNH Master Gardener and the author of four gardening books. His website is Gardening-Guy.com. Reach him by email at [email protected].

Early spring chores

Take a look around without flowers distracting you

Early spring is a good time to look at the trees and shrubs on your property, when you are not distracted by flowers and leaves. Study your “woodies” now to see if they need some care — and if some plants need to be removed for the health or beauty of the remaining ones.

If you have a wooded area on your property, it probably needs some help from you, especially if you haven’t done any thinning or grooming of trees in recent years. Start by going outside and really looking at the trees growing on your property with a critical eye.

In nature trees grow willy-nilly. Where a seed lands is largely determined by chance. It is unable to know if it is 6 inches or 6 feet from another tree. If it germinates and grows it might be a good place, or it might be smack-dab next to another tree — or your house.

Ask yourself this question as you walk around your property at your trees: What is the future of this particular tree? How big does this type of tree grow to be? What will this one look like in 10 years? In 50? Is it too close to its neighboring trees or to the house? Is it shading your vegetable garden or favorite flower bed?

I’m a tree-hugger but I have no problem with cutting down trees when judicious removal is beneficial. Now is the time to plan on some careful thinning of trees to improve the health of your best trees and to improve the looks of your landscape.

Before you start tagging trees for culling, you need to learn to identify the trees on your property. A good guide is A Guide to Nature in Winter by Donald Stokes, a wonderful book that will help you with that. Because there are no leaves on most trees out there now, the Stokes book is great — it identifies trees by their bark, shape and buds. It also teaches much about all the other living things out there in the woods, from snow fleas to deer and everything in between.

Trees that I cull from my woods include poplars (Populus spp.), boxelder (Acer negundo) and alders (Alnus spp.). These are fast-growing trees that are short-lived and that produce lots of seedlings.

Trees that I revere are maples, oaks, beeches, birches and hophornbeams (Carpinus caroliniana). I would think long and hard about cutting down one of them. But if a fast-growing poplar were growing within 6 feet of one of my favorites, I would not hesitate to cut the popular down. Trees need plenty of space to do well.

Invasive shrubs make their way into most woods, too. Barberries, burning bush and honeysuckles are shrubs that can choke out native shrubs and many native wildflowers. I work on eliminating those every spring, but the honeysuckles are still ahead of me. Learn to identify them and tag them for removal.

There are a few buckthorns (Rhamnus spp.) moving into the neighborhood, and I am keeping a sharp eye to make sure none get established on my property. Buckthorns are invaders that cannot be easily killed by cutting them down because they sprout up from their roots if you cut them down.

To rid your property of buckthorns, you can pull young ones or girdle the older ones. Trees up to about 2.5 inches in diameter can be pulled with a tool designed for that purpose. It is often called a weed wrench, although the original Weed Wrench company has gone out of business. Another brand of weed wrench is called the “Pullerbear.” It is a steel tool with a gripping mouthpiece and a long handle that provides mechanical advantage. They come in several sizes and prices. For more info see www.pullerbear.com. I have not yet tried one of this brand, but they look like the old weed wrenches I have used.

If you cut down a mature buckthorn it will stimulate the roots to send up many suckers that will develop into new trees. To prevent this from happening, you need to girdle buckthorns twice about 12 inches apart. Cut through the bark severing the green cambium layer all the way around the trunk, but don’t cut deeply. They will usually survive two years before dying. Girdling starves the roots of food from the leaves.

You can girdle them now but doing so right after they leaf out in the spring is better. Just tag them now, and plan their demise. Some buckthorns develop multiple stems in a cluster, making it tough to girdle them, but it is possible using a pointed pruning saw.

Hemlocks and pines often grow so densely that their lower limbs die out because the sun never reaches their leaves. Removing those lower branches opens up the landscape — another task you could do now. And think about removing any wild grapes that are climbing your trees — they can kill them.

So enjoy the spring weather and make some plans for real spring.

Henry Homeyer is the author of four gardening books. You may contact him at [email protected], or P.O. Box 364, Cornish Flat, NH 03746. His website is www.Gardening-Guy.com.

Featured photo: A weed wrench allows anyone to pull out invasive shrubs. Photo by Henry Homeyer.

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