My book and web site

Check out my book, The Sustainable-Enough Garden, available on Amazon, and the book's web site at www.thesustainable-enoughgarden.com. See more plant photos on Instagram.

Sunday, December 31, 2017

Less is more

Happy New Year! Amy Andrychowicz advises in the Savvy Gardening Newsletter that gardeners write “garden reflections” at the end of each year, documenting what went well and badly in this year’s garden and what can be improved next year. Here are some of mine:

    What went well? A lot that wasn’t in my control. We got plenty of rain! That kept the garden lush and flourishing. 



Rain made everything grow

    Also good was that the destructive nonnative winter moth dwindled my area. Tachinid flies (Cyzenis albicans) released by UMass professor Joe Elkinton are killing winter moth larvae. I counted three or four moths at the front porch lights this fall, nothing like the clouds of them we’ve seen in previous years. With so few parent moths, I predict few caterpillars will show up next spring to defoliate and weaken our trees.


There should be less winter moth damage next year
  
    Thanks to a much-abbreviated work schedule, I was in the garden most days all season. That gave me a chance to start addressing a list of dozens of tasks and projects I’d put off over the past decade. 


    This year I got to tear out a big patch of lawn and replace it with new perennials, mostly native species. It doesn’t look like much yet, with little plants surrounded by wide stretches of mulch. In three years when it’s filled in, I’m expecting a lush habitat for birds and native insects, as well as a pretty sight from the back of the house and the deck.


With luck, these little plants will grow wide and tall


    Restricting my container choices to neonicotinoid-free plants also turned out well, better than I’d expected. Maybe a smaller palette of choices prevented over-complicated compositions.


Simpler container combinations did better

    What didn’t go so well? Despite the plentiful rain, my vegetable garden didn’t produce a lot. Two problems stick out. First, I planted intensively with not much space between plants and rows because I’ve got so little sunny ground. That meant overcrowded plants didn’t get all the sun they needed. I didn’t leave enough space for paths, so while trying to spring lightly in and out of the beds, I stepped too close and packed down soil where roots were trying to grow.


Tight quarters in the vegetable garden

    This was the year I noticed my trees were crowded too, bent out of shape by competing to reach the light. That’s because of mistakes I made twenty years ago planting them too close together, like those vegetables. Having done that, I could have pruned more aggressively than I did. Back when the trees were young, I was afraid I’d kill them if I cut back their young branches to direct their growth. Now I know better.


Cramped trees

    The takeaway? Less is more. Make the hard choices and plant what I really have room for. Plan for the full-grown size, whether of 12-inch-tall bean plants or trees that will reach 60 feet. Failing that, don’t be too sentimental to thin out the extras when it’s time. Will I live by this insight and refrain from overcrowding the new perennial bed? Time will tell.

Sunday, December 24, 2017

While the weather outside is frightful

Outdoors it’s winter, but plants still grow and even flower indoors, despite short days. During winter, I try to nurture houseplants in a sustainable way by limiting turnover, minimizing use of materials with high carbon cost, and carrying over outdoor plants that can make it through the winter next to a window or under lights.

Geraniums and succulents making it through the winter under a grow light

    Some of my houseplants may be older than my children. I can’t resist treating them like pets and keeping them even when they aren’t beautiful. This winter I’ve added some pretty young variegated ivy and a fern to the collection. 


Variegated ivy can thrive indoors and out

I’ve had good luck transplanting low-light selections like these in spring to a large box planter in a shady area. This way I can enjoy their foliage through both the winter and the summer. The fern will succumb to next fall's frost, but the ivy may tough it out and become a perennial.

    Winter blooms of African violets, orchids, paperwhite narcissi, and amaryllis will add some welcome color to this mostly green scene.


African violets blooming in February

    I also rooted cuttings from some of the neonicotinoid-free geraniums, coleus, begonias, and rosemary that I bought last spring to plant in summer containers.

 
A confused geranium blooming this week

It was difficult to find plants that hadn’t been sprayed with the pollinator-toxic insecticides. I’ll be able to use the old plants’ descendants next year and avoid the search for untreated plants. The youngsters aren’t going to get me into House Beautiful, but I think they look cheery under a grow light in the kitchen/family room. They’re located where I can’t miss seeing them, so I notice when they need care.

    By recycling plants from last summer, I avoid the carbon cost of new plants. This can be considerable, because they often travel to local garden centers from remote parts of the country and the globe. I also reuse the plastic pots and six-packs that my plant purchases came in. 


Ready for starting seeds in early spring

Washing the soil out of these and storing them in the basement is a winter activity. Like the indoor bulbs, cuttings from summer plants are grown in homemade peat-free potting mix. By using this growing medium instead of commercial potting mix, I spare the peat bogs, which sequester much of the world’s soil carbon.

    I’ve long had a fantasy of enclosing a small porch at the side of the house in glass to use as a greenhouse or conservatory. 


The conservatory at Tower Hill Botanic Garden

In addition to the cost, a concern that holds me back is how I’d cope with infestations and plant diseases indoors. The greenhouse manager at the Arnold Arboretum once told me that they emptied the greenhouse once a year to clean it thoroughly and spray it with diluted chlorine bleach. The prospect of donning a hazmat suit and mask to spray an indoor space with chlorine or other toxic pesticides cooled my enthusiasm for a greenhouse attached to our living space.

    Unlike the Arboretum staff, I’m not growing irreplaceable specimens. If indoor plants get sick or attract insects, they’ll find themselves filling another sustainable role—as compost.


Happy holidays, inside or out!
 

Sunday, December 17, 2017

Better red than dead

In my yard, this year’s fall foliage was pretty much a dud. In particular we didn’t get the bright reds we usually see on our Japanese maples, 

Most years a maple in the front yard turns bright red

neither on a purple threadleaf variety in the backyard (Acer palmatum var. dissectum) nor on a broader-leafed version in the front. Most years they see the foliage season out with glowing scarlet leaves. This year the leaves just turned brown, shriveled, and hung on. Last weekend’s snow hung dishearteningly on the brown leaves.

This year leaves turned brown and hung on

    I feel cheated. Why did this happen? I thought this had been a favorable growing season. Some Internet research convinced me that it’s hard to know exactly why fall foliage is dramatic one year and drab another, because several factors interact to produce the autumn display. But it’s clear that events conspired this fall to prevent formation of the red pigments, anthocyanins, that give red maples and Japanese maples their gorgeous red fall color.


Late October 2015, same tree as the one above

    We were relieved this spring when rainfall stayed ahead of the annual average. By early summer, New England precipitation was well ahead of expectations, making up for last year’s drought. As of December 15, we were still ahead, with 42.30 inches of precipitation for the year, compared to the normal year-to-date total of 41.79 inches. 

    But the fall months demonstrated the swings between extremes we can expect with climate change. Around Labor Day it was unusually cold, then we had a heat wave later in September with temperatures up to 90. Heat and humidity kept the leaves on the trees. Although the tail end of Hurricane Philippe swept through our region late in October, bringing flooding and high winds, this fall season was short on rainfall. That already meant that foliage color was likely to be dull.


This fall's conditions weren't favorable for bright leaf color

    What signals trees to prepare to drop their leaves is a combination of longer, cooler nights and less intense sunlight. They get ready for winter by stopping production of chlorophyll, the pigment that enables photosynthesis and makes leaves look green. With only their yellow xanthophyll and orange carotenoid pigments remaining, leaves look yellow.


 
Witch hazel leaves turn yellow without chlorphyll

    For red and purple color, leaves need sunny days and cool but not freezing nights. These conditions trigger production of anthocyanins from sugars left behind in the foliage when trees cut off transport of materials in and out of the soon-to-be-jettisoned leaves. 


Red color made from stored sugars

My conclusion is that this November’s cold snaps with temperatures in the twenties cut off this process before our Japanese maples could turn red.

    Every gardening year is different, of course, and we can’t attribute all weather variations to global warming. There does seem to be a trend at work here, though. Researchers in phenology, the study of changes that occur seasonally, say that warmer temperatures lasting later into the fall are causing delayed leaf senescence and therefore later appearance of bright fall foliage. 


     We can only hope that next year Japanese maples will have time to turn red before winter cold intervenes. 

It's nice when each plant shows its fall leaf color
 

Sunday, December 10, 2017

Life support

With the first snow this week, my spirits plummeted. Winter is really here, and I wish we could fast-forward to April 1st.  

Not this again!

Since we can’t, it seemed like a good time to plant some indoor flower bulbs to get me through the cold, dark months.

    My bulb choices this winter are paperwhite narcissi (Narcissus papyraceus) and amaryllis (Hippeastrum species).


Paperwhites have a lovely scent-photo by Ceasol


You really can’t fail with these bulbs, which contain everything they need for flowering when you buy them. 

You can't beat amaryllis for big beautiful flowers in the dead of winter-photo by pizzo disevo

A bulb is a storage mechanism that allows the plant to get through dry periods. It’s made up of embryonic leaf, stem and flower tissues surrounded by fleshy scales that contain food stored up during the plant’s growing period. An onion is a bulb too; the rings of flesh are its storage scales.

    Once you plant them and they start taking up water, bulbs send out roots from their base plates, and stems start to extend upward. They’re going to do it whether you help them or not. In fact, unplanted bulbs start putting up flower stems if I leave them in the basement for too long before planting them. 


    I prefer to pot the paperwhite bulbs in homemade potting mix. I make the mix by combining coir (coconut husk fibers) with compost from my compost piles to avoid using peat-based medium, which is not a sustainable product. I find that paperwhites grown in the potting mix stay more upright than bulbs grown in bowls of pebbles.


Once covered with potting mix, the bulbs can be watered and set in a cool, dark basement spot for a week or so until they start sending up new growth

    Amaryllis bulbs are gigantic. The one I planted weighed more than 15 ounces, with a diameter of 5 inches. 


Hubba hubba!

I usually get four flowers on each stalk. A second stalk often emerges a few days after the first. I nestled this bulb in a pot just wider and taller than itself. Only a little potting mix was needed to fill in the remaining space. 

I set the amaryllis pot next to a radiator to help it start growing. I'll move it to a cooler windowsill once the flower stalk starts extending

    Anyone who has a window with a bit of sun can get flowers from these bulbs. The harder challenge is to get them to flower again the following year. The paperwhites originate in the Mediterranean. They need a warm climate and won’t survive in New England gardens. For us, they’re annuals.


    It’s tempting to try to get amaryllis to rebloom. In their natural habitat in South Africa or South America, after flowering the bulbs would soak up sun and soil nutrients for a couple of months before dropping back into dormancy, waiting for the signal to flower again. It takes a lot of sun to pack in the same amount of stored energy in our area. Here are some instructions from the National Arboretum.


    My experience has been that with lots of trouble, I can get amaryllis leaves to grow the next year and, rarely, one small flower cluster. It’s not worth it. I pay the $15 for the big bulbs and throw them on the compost pile when they’re finished blooming. All good things have to end—and winter does too.



Sunday, December 3, 2017

Shredding less and enjoying it more

I’m enjoying not shredding leaves this fall because of a new approach to mulch. This year I’m going to let whole leaves lie on the garden beds. It’s all for the insects.

Whole leaves as mulch


    I’ve been evolving a strategy for mulching with fall leaves for more than 30 years. Back when I started my garden, I tried piling whole leaves on garden beds, but it soon became obvious that they wouldn’t stay put. Instead, they blew around and landed on my neighbor’s lawn. Since he raked meticulously almost every day, I could see this was going to be a problem. 


    That’s why I started using a leaf shredder—essentially a string trimmer in a drum—to chop up fall leaves into mulch. 


Leaf shredder

The shreds were pretty, they definitely improved the soil as they decomposed, and they didn’t blow around the way whole leaves did. I could use them for mulch in the front yard without making myself unpopular in the neighborhood. 

Shredded leaves make pretty mulch

    For years I shredded leaves every fall to mulch the beds close to the house. By default, the beds farther from the house ended up covered with unshredded leaves.


    Last year I heard something that persuaded me to change my approach. Claudia Thompson of Grow Native Massachusetts spoke at my garden club and explained that native insects benefit from leaf litter. By shredding leaves, I was chopping up insect eggs laid on the leaves and eliminating habitat for adult insects that need to overwinter under fallen leaves.


    This year instead of shredding the leaves, I’m just raking them from my lawn and my neighbors’, piling them on a tarp, and dragging them over to dump on the garden beds. 


Leaves on their way to backyard beds

Because I eliminated a whole area of lawn this year and replaced it with a bed of native perennials, I don’t have to worry about errant leaves damaging lawn grass. If leaves from the new bed blow around, they’ll just land on paths of woodchip mulch or bluestone.

New bed surrounded by paths, no lawn grass


    While I pat myself on the back for upgrading my sustainable practices, I’m also doing a lot less work. Just moving the fallen leaves to the beds is much easier than feeding them into the shredder drum. It was never fun replacing worn filaments, breathing leaf dust, or having my face stung by flying fragments (goggles and heavy gloves were a must). I still plan to shred a few leaves for the front yard.


    We’ll see how this new approach works next spring. Conventional wisdom teaches that whole leaves mat down and have to be removed to let perennials reach the light in spring. Claudia said she doesn’t have this problem in her garden of native shade-lovers. 


Will bloodroot flowers be hidden by matted leaves?


     Worst case, I’ll have to move some leaves in spring when it’s warm enough for insects to emerge from winter lodgings. Meanwhile, I can give the shredder a miss and tell myself I’m conducting an important experiment!