Spring planting

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.

Stems, branches and weeds

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.

Get out the pruners

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.

Starting from seeds

It’s time to get ready!

I love starting seedlings indoors when it’s still cold and raw outside. It makes me dream of summer and the first red tomato. For me, it is still too early to plant most things, and I certainly don’t want to have to baby my seedlings along for 12 weeks or more. But if you haven’t ever set up grow lights and don’t have all the equipment for indoor growing, now is the time to get everything you need before the stores sell out.

First, some basics: You need lights over your seedlings in order to get good plants. Yes, I know some people grow things on a bright windowsill for a few weeks, but getting sturdy tomato plants or zesty zinnias requires supplemental lighting.

Second, you can’t use garden soil to grow your seedlings. Ordinary garden soil is too heavy and gets compacted with watering, and it may harbor fungal diseases. You need to purchase potting soil.

Last, you need a place that is at least 60 degrees but no more than 70 degrees. Cooler temps at night are good. Electric heat mats placed under your seedlings will help get quick, even germination but are not required.

There are several types of lights for growing seedlings. For years I used fluorescent lights: 4-footers with fat T-12 tubes. These work but now have been replaced with more energy-efficient, slimmer, T-8 tubes. There are also LED grow lights of various sorts that use even less energy, though those can be very expensive.

Sold as shop lights, T-8 two-tube fixtures should cost around $20 each, plus the fluorescent tubes, which cost around $8 each. But do not, I repeat, DO NOT spend the money to buy full-spectrum tubes, which cost upward of $35 each. You are not raising plants for sale, and for the short time they will spend in your basement, regular cool white tubes are fine. Or mix cool and warm white to get a broader light spectrum.

If you have a warm basement, I’d suggest that the easiest approach for starting a few things would be to use a card table and 4-foot fluorescent fixtures hanging from the ceiling. Put plastic over the table to protect it from water spills.

You can also go to my website, gardening-guy.com, and search for “Building a Plant Stand.” That will give step-by-step directions for building an inexpensive A-frame plant stand that will hold six flats, and have room below it for four to six more flats on the floor.

Your hardware store can sell you something called “jack-chain” that will allow you to adjust the height of your lights as your plants grow. Ideally, your lights will hang about 6 inches above the top of your plants. Two 4-foot fixtures, each with two tubes, hanging a few inches apart will illuminate four flats (or trays) of seedlings. When you buy your flats, be sure to get those that do not have holes in the bottom, as some do. The flimsy “six-packs” that fit into the flats come in various sizes, but I always look for the biggest, deepest cells. So, yes, you can get tiny cells that will allow you to plant 48 or even 72 plants in a flat, but there is not much room for roots.

The flimsy six-packs tend to self-destruct easily, particularly if you try to wash them out for re-use. But there are heavy-duty planting trays and cells that will last many years. Gardener’s Supply sells them, along with clear domes to go over them. They cost more but will last forever, and some have self-watering features.

What about the soil mix for growing? Buy good-quality “seed starting mix” labeled as such. I mix it with high-quality compost in a 50-50 ratio. Sometimes I make my own starting mix using peat moss, perlite, vermiculite, compost and a slow-release organic bagged fertilizer. I start about 10 flats of plants each year, so there are cost savings for making my own mix.

Seeds are very susceptible to drying out, which can be lethal. One way to keep that from happening is to check on them often. Once a day is fine. Or, if you have a busy schedule, buy clear plastic covers that fit over each flat. These, like the flats, are reusable. They will steam up and rain the moisture back onto your plants, just like a tropical jungle. Remove them when most cells have plants that have germinated.

How deep should you plant your seeds? About three times the length of the seed. Tiny seeds need just a thin sprinkling of soil mix over them. Bigger things like pumpkin seeds can be covered with half an inch of soil mix. Press down lightly with your fingers after covering the seeds so the soil mix is in good contact with the seed.

Lastly, water them. I like a soda bottle for watering, as it can deliver a nice slow trickle. Water the soil mix before planting, because if it is too dry, it is resistant to absorbing water.

The bottom line is that starting seeds is fun. And it lets you choose plants you might not find at the garden center. So get your materials and set up your lights. I start tomatoes and other frost-sensitive plants six to eight weeks before I would put them in the garden.

Dream Big

Make a wish list of trees you want

I was recently thumbing through my first book, Notes from the Garden, looking for inspiration for yet another winter article. In it I read that I had planted my Merrill magnolia in 2001. I had forgotten that I planted it just 20 years ago this spring — it feels like it has always been there!

Looking out the window at that handsome tree that blooms each April with a thousand large, lightly fragrant double white blossoms made me think: How many of us plant a tree with a vision of what it will be like in 20 years? I had mainly hoped it would survive to bloom modestly, but it has been a magnificent tree for a decade or more.

I invite you to draw up a wish list this winter. Think of big, majestic trees that you wish to have and figure out where you could plant them. Dream of flowering trees. Think of native trees that will feed the baby birds with the thousands of barely noticeable caterpillars that feed on their leaves. Imagine a recliner in the shade of a tree you have planted. Picture grandchildren playing in its shade.

I think it’s important to realize that trees get to be of a good size fairly quickly. Most grow two to three feet per year, some even more than that. So what if you are 60 or 70 or 80 years old? Even if you never live to see it bloom or drop nuts on the lawn, you are improving the environment, now and in years to come.

Years ago I visited author, illustrator, eccentric and well-known recluse Tasha Tudor at her home in southern Vermont. She was in her late 80s at the time but still was planting trees. She asked me if I could help her find two specific crabapple varieties that she had planted 30 years before but was unable to find anywhere.

One variety I found at EC Brown’s nursery in Thetford, Vermont. The other I could not find, so I asked her where she had purchased it. She told me that she bought it at Weston Nurseries, and I called them. The woman who answered the phone remembered her, and the fact that she traveled with a rooster under her arm. Amazingly, she also remembered the fellow who waited on her that day; he still worked there, and he was brought to the phone. He explained that the variety was no longer in production. End of story.

Actually, it was not. I saw Wayne Mezitt, the owner of Weston Nurseries, at a trade show, and told him the story of his people remembering Tasha. He said he would make her some of the trees she wanted by grafting branches onto root stock. And he did. Three years later, Wayne and I met and presented Tasha with the trees she wanted. By then she was past 90 but still planting trees. Did she ever get to see them blossom? Unlikely, but I love the idea of someone her age planting trees. I hope to do the same.

If you plant trees over a long period of time it is hard to keep track of when you planted them,and the variety planted. Keeping track takes real discipline. In my experience, tags are fine for a few years, but eventually they get lost or the writing fades until it is unreadable.

If you are linked closely to your phone or tablet, that might be one way to keep track of what you plant — until the phone dies or gets replaced. I don’t have a cell phone, so I cannot advise how to keep records on it. But I do take lots of photos and they are in my computer by date, so I should be able to find most anything I plant — so long as I label well — and the computer doesn’t eat things, which mine does from time to time.

I like writing things down, using a real pen, sometimes even using my trusty fountain pen. Years ago I bought a 10-year Gardener’s Journal from Lee Valley Tool Co. They still sell them, and at about the same price: $32.90. It is hard-covered and durable. The only thing it lacks is a search function. It has a page for every day of the year, and 10 sections per page — a few lines for every day. In principle I would write the weather, what I planted or pruned or dug out every day. But life gets in the way of even the best of intentions.

I like old-fashioned “3×5” cards for making lists: to-do lists, grocery lists. They fit nicely in a pocket and good ones are quite sturdy. My Winter Resolution (like a New Year’s resolution, but made after Groundhog Day) is this: I will fill in a note card every time I plant something. I have an old-fashioned wooden box designed for 3×5 cards, and I will use it to keep track of my plantings this year.

So what will go on the cards? First I have to decide if I will use common names or scientific names for alphabetizing the plants. I will use the scientific names, as that is how I think of most of my plants. But I will also include common names. Date planted, source of the plant, where planted, perhaps soil amendments added or any other details that might be useful. If plants die, I will keep the card, but place a black dot on the upper right corner of the card.

Last fall I wrote up a list of woody plants I have planted here in Cornish Flat since I bought my house in 1970. I listed nearly 80 species or varieties. I think I’ll fill in a card for each tree on the next raw, gray, wet day.

Featured Photo: Wayne Mezitt presents Tasha Tudor a White Weeper crab apple. Photo courtesy of Henry Homeyer.

Build a garden library

Basic books to get you started

I know that many people, especially gardeners under the age of 40, use the internet to find the answers to their questions. That is fine, but the internet is full of “fake news” and spurious assertions. I do use the web, but if I want to learn about something in depth, I reach for a book. People who write books generally write about things they know. Garden books are written by gardeners.

Some years ago I taught a class in sustainable gardening at Granite State College, part of the University of New Hampshire system. I asked my students to buy The Garden Primer by Barbara Damrosch. This paperback is a compact 800 pages of readable, educational information about nearly every aspect of gardening. It came in out on 2008, but is still in print. Everyone could benefit by owning it.

For a book on vegetable gardening there is none better than Vermont’s own Ed Smith’s The Vegetable Gardener’s Bible. With more than a million copies sold, this book goes into detail on every veggie you could grow — when and how to plant, how long seeds last, when to harvest, and much more.

Are you interested in flower gardening? My first choice of books would be Tracy DiSabato-Aust’s book, The Well-Tended Perennial Garden: Planting & Pruning Techniques. She is obviously a well-experienced gardener and designer, and one who has learned to get her flowers to re-bloom, or bloom at a shorter height, and who knows how much sun and water each needs. Staking? Dividing plants? It’s all there and more.

For the serious flower gardener or landscape professional I would recommend a 1,100-page book by Allan M. Armitage: Herbaceous Perennial Plants: A Treatise on their Identification, Culture, and Garden Attributes. This book came out in 1989 and it is now its fourth edition, which came out in 2020. My goal for the winter is to read it, or the relevant parts, cover to cover. Why? Because I can learn from a man who is not only a Ph.D. professor but a hands-on gardener of many decades.

There are plants in the book that I absolutely lust for. Unusual plants that will fill niches in my diverse garden beds. It also tells me why some plants I have tried have died out. It informs me about named varieties to look for that have special attributes.

Dr. Armitage is opinionated and often funny. I like that. It has some photos, but certainly not one for every flower mentioned. This is not a coffee table book, but a book for plant collectors, landscapers — and fanatics. At just under $80, I think it’s a bargain.

Trees? The most prolific and best informed expert, in my opinion, is Michael Dirr. I use his Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propagation and Uses every week of the year. It has informed me about any tree or shrub I want to know about. Now in its sixth edition, it sells new for $81.80, but it is available used for much less (usually earlier editions).

Professor Dirr also has written many other books, several of them with terrific color photos (in contrast to his Manual, described above, which has only drawings). I spent one winter going through his Dirr’s Encyclopedia of Trees and Shrubs with its descriptions of 3,700 species and cultivars and 3,500 photos.

Pruning is key to keeping your woody plants looking good. My favorite pruning book is by Lee Reich, The Pruning Book. With both diagrams and photographs, this book covers many species and their specific needs. His book Grow Fruit Naturally is another excellent book you might want.

Soil is the key to good gardening but a topic that is usually boring and scientifically described. Want an easy explanation of how it works? Try a book by Dianne Miessler, Grow Your Soil: Harness the Power of the Soil Food Web to Create Your Best Garden Ever. It explains very well how soils work, what soil test results mean, and how to correct deficiencies. You don’t need to be a scientist to read this one ($16.95 in paper).

Stone is a key element in many gardens, part of the “bones” of a garden. Dan Snow, a Vermont dry stonewaller and stone artist, has written a number of fine books on using stone. Listening to Stone and In the Company of Stone both offer practical and philosophical advice and share many fine photos of his projects.

Gordon Hayward, a Vermont landscape designer and prolific author, also has an excellent book on how to use stone, Stone in the Garden: Inspiring Designs and Practical Projects. Want to build a stone path or a retaining wall? Hayward simplifies the process. As with Dan Snow’s books, great photographs full of ideas.

Sydney Eddison is another prolific garden writer with many fine titles. Her The Gardener’s Palette: Creating Color in the Garden taught me a lot about the use of colors in the garden. Her advice is always practical and nicely explained.

So invest in some books this winter, curl up in a comfy place and see what you can learn that will help you, come spring.

Featured Photo: Two fine books on perennial flowers. Courtesy photo.

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