Thursday, February 23, 2012

Witchhazel blossoms on February 5th! Not here, but down in Longwood Gardens in Kennett Square, PA, a public botanical and pleasure garden around which I had some time to wander before giving a lecture. One little grove was particularly fragrant and comely, with a few witchhazels shrubs with yellow blossoms, some with bright orange blossoms, and some with brownish orange blossoms.
February 5th is early for witchhazel even down there, reflecting what has been the mildest winter in memory. While many people prefer mild winters, this weather worries a lot of gardeners. Are plants going to become “soft?” Is possible cold weather in the weeks ahead going to do them in?
Call me a pollyanna, but I have a lot of faith in Mother Nature (or, put another way, natural systems) to adapt and protect against calamities. Not that everything will necessarily keep chugging along the way we humans like it, but that forests will remain forests, perhaps with some changes in species, and that garden plants should, in general, survive.
A few odd things are going on this winter here in the Northeast and over much of the rest of the country. First is the mild temperatures. People worry that plants might begin to grow too soon. But today’s and tomorrow’s temperatures aren’t the only things that shake plants awake this time of year. Daylength also comes into play, and no matter what the winter is like, daylength is the same on any given date from year to year. 
Temperatures over the past weeks and months also come into play: Plants won’t begin growth until they’ve experienced a certain number of hours of cool -- not cold -- temperatures, signaling for them that winter is over and it’s safe to grow. Some winters, those hours begin to accumulate in autumn and then finish accumulating in late winter, when temperatures turn cool, not frigid, again. In the South and perhaps this far north, this winter at least, those hours could have accumulated sufficiently through winter to cause an early awakening of plants.
The first sign that many trees and shrubs show of awakening is the appearance of their flowers. These early blossoms could, in fact, succumb to subsequent cold weather. That cold could snuff out developing fruits, snuffing out this year’s crop. Or that cold weather could turn, say, an early tulip blossom from a handsome red cup to a wet dishrag on a stalk. In either case, the plants themselves, except for the blossoms and fruits should not be harmed. 
The second odd thing about this winter is the lack of snow cover. Snow reflects light and heat from winter sun. Evergreens don’t like this at a time when their roots are cold and not especially active. The result is scorched leaves. Bark also can scorch, except this time it’s called scalding, when winter sun heats up dark bark by day and then bark temperatures plummet as the sun drops below the horizon.
On the plus side, snow is a great insulator. It helps modulate soil temperatures to minimize alternate freezing and thawing, which can heave plants up and out of the soil. Heaving is especially a problem with young or new plants, as yet hardly rooted. That insulating, white blanket also lessens roots’ exposure to cold. Without snow, less cold-hardy plants (and we gardeners are always pushing the limits) might show more winter damage.
Then again, snow isn’t the only insulator. Any good gardener mulches plants to provide nutrients, to conserve water, to build up humus, and to feed beneficial soil life. I’m banking on those layers of wood chips, leaves, straw, and other organic materials I spread through autumn to protect my roots -- plants’ roots, that is.
No question about it: Temperatures, on average, have warmed in recent years. Plants are responding. But how? Trees, for example.
To help answer such questions, the Smithsonian Institute recently began a citizen science program to track tree growth throughout the world. The way it works is that, after signing up to become a “citizen scientist,” you’re sent a tree banding kit along with instructions for attaching the tree band, selecting study trees, and gathering and reporting data. Information, including a video, is available at
It’s all free, it’s all interesting, and your data, along with that of citizen scientists worldwide, will help us better understand tree growth, and what’s affecting it, over the years.
Turning my thoughts back to Kennett Square and Longwood Gardens . . . I’m jealous. Not of their awesome, main conservatory fragrant with citrus trees and lilies in bloom. (I have a small greenhouse, and a kumquat, a citrus relative, that blooms in summer.) Not of their small greenhouse that is home to espaliered peach and nectarine trees and to a dozen or so potted fig trees. (Three fig trees grow in my greenhouse.) Not of their grove of witchhazels in various shades of yellows and reds. (I have one yellow witchhazel.)
What I am jealous of is the care that each of their plants receive; each one is perfect. If an old leaf or spent flower drops on the ground, someone picks it up. Each stem of their peach and nectarine espaliers is tied neatly to its trellis, as are the high vines clambering up pillars in the greenhouse. Outdoors, each tree is pruned to perfection, with none of their branches crowding, with any diseased or dead limbs lopped off cleanly. Looking closely enough, I did, at least, see some evidence of scale insects on their large potted grapefruit plants in the conservatory. (My large potted bay laurel also shows evidence of scale.)
My gardens, indoors and out, would be much improved with their knowledgeable crew of helpers.

Thursday, February 16, 2012

        See previous post, below, about my new book, just out!! GROW FRUIT NATURALLY: A HANDS-ON GUIDE TO LUSCIOUS, HOMEGROWN FRUIT.
Every time I walk out the back door on the way to the greenhouse, chicken coop, or compost pile, I take a look at my vegetable gardens. No, I’m not checking out what’s growing. Nothing’ growing, except for a few stalks of kale and some green tufts of m√Ęche.
My real interest is how the vegetable garden looks, now, in midwinter. Too many people plant their vegetables in “vegetable prisons:” undersized gardens with oversized fencing relegated to a distant corner of the yard. 
A vegetable garden needn’t be an eyesore, even in winter when nothing is growing in it. Consider the fence, which endures year ‘round. How about white pickets, rustic cedar or locust, or fanciful arches of rebar filled in with mesh? And no need to segregate plants, banning ornamentals from the vegetable garden. How about dwarf boxwood as accent or edging within the garden and shrubs outside the fence to soften its transition to lawn? How about some cover crops in the vegetable beds for a verdant cover, turned tawny this time of year, which also improves the soil? How about an arching arbor as an invitation to enter the garden, the arbor perhaps dressed up with clematis, whose fuzzy seedheads persist long after the flowers fade.
Once a vegetable garden becomes inviting, there’s no longer the need to relegate it to that distant corner of the yard. Move it closer to the house or, even better, the back door or, better still, right against the house, linked to it with eyes and feet. (Brick house, brick paths; white clapboard house, white picket fencing; etc.) Now you have a garden that not only looks prettier, but one that also will get more care and use because of its proximity and visual draw, ad looks good even in winter.
My two vegetable gardens are hardly eyesores, but as I look upon them now, I see that they could be prettier. And one of them could be even closer to the house. (It’s now about 25 feet distant.) 
I originally rented my house and the closer vegetable garden still stands where the original one was once differentiated from the then-weedy, tall grassy field by a rickety chicken-wire fence. The fence has been re-built twice, most recently with locust posts and cross-pieces, and welded wire fencing. I have dressed up its outside perimeter with billowing outpourings of trees and shrubs, including some red currant bushes which ripen tasty, brightly-colored, jeweled fruits in early summer, and a cornelian cherry tree, also with tasty, bright red fruits later in summer. In a month and a half, that cornelian cherry tree will be showered in yellow blossoms. (More on all this in my book Landscaping with Fruit.)
Although I am loathe to move the vegetable garden, with its 30 years of compost-enriched soil, closer to the house physically, I have attempted to do so visually with a series of gateways and arches. Standing in my kitchen and looking out a glass, sliding door towards the garden carries your eyes under the grape arbor over the terrace attached to the house, across a small patch of lawn, and thence through a rustic, locust arbor into the garden. The path through the garden carries you further, across the garden and then out through another arbor, the path extending into a berry patch. Further along, that path ends in yet another, arbor, this one simpler, and finally outside the planted areas to a short path that meanders mysteriously out of sight into a patch of bamboo.
Still, my landscape seems too disjunct. The gardens aren’t sufficiently tied to each other or to the surrounding landscape and house.
The vegetable garden also is now too gray and brown. The evergreen white cedars, boxwoods, and Meserve hollies around and near the gardens cheer and warm up the landscape, but more is needed.
The traditionally coldest part of winter is past and it hasn’t been very cold, so I may risk expanding the outdoor evergreen palette, which is somewhat limited this far north. Temperatures did drop to about 5°F a few weeks ago, but nighttime lows at the end of January were only in the 20s, nothing like the lows of minus 25° experienced many years ago.
The USDA, recognizing the shift to warmer winter temperatures, recently updated their cold hardiness zone map, available at Wavy lines overrunning this map bracket each zone, from 1 through 11, delineating the average annual minimum temperature within each zone. (My garden, over the years, has been re-classified  from 4b to 5b.) Nursery catalogs and tags on plants in local nurseries spell out, among other bits of information, the hardiness zone limits for specific plants and varieties.
Helping me out on my search for new evergreens will be Michael Dirr’s new book, Encyclopedia of Trees & Shrubs, a weighty and informative tome in all respects. In a few years, with continued warming, I may try planting two southern evergreens that I long for here in the north: southern magnolia and camellia.

Wednesday, February 15, 2012

Hot off the press!!!! My new book, Grow Fruit Naturally: A Hands-On Guide to Luscious, Homegrown Fruit (The Taunton Press). Grow Fruit Naturally is THE book for you if you want to pick luscious fruit right from your own sunny balcony, suburban lot, or farmden. Sure, growing your own fruit will save money but -- even better -- your home-grown apples, blueberries, peaches, or oranges will be the best you’ve ever tasted and won’t be doused with toxic sprays. 
Grow Fruit Naturally shows you the way to successfully harvest fruits that are delicious and healthy, with information on over 30 fruits, from temperate to tropical, and how to reap the most of their bounty. Natural growing begins with creating a healthy soil environment for roots and their microbial friends, and choosing the best kinds and varieties of fruits to plant both for top-notch flavor and for pest and disease resistance. Grow Fruit Naturally will lead you from those first steps right through harvesting for peak flavor and storing any excess. Some topics include:
• Planning for growing fruit
• Choosing plants for flavor and pest 
     and disease resistance
• Propagating fruit plants
• Pruning a fruit tree, bush, or vine
• Growing fruit plants in containers
• Avoiding or controlling common pests 
     and diseases naturally
• Storing your bounty
The emphasis here is also on simplicity, guiding you through pruning and other care needed to make growing everything from apples to figs to oranges to pawpaws to strawberries feasible within any constraints of time and space. Grow Fruit Naturally will soon have you harvesting luscious, wholesome fruits outside your own back (or front) door.

 Grow Fruit Naturally is not available through the usual outlets until mid-March. If you're anxious to get started to heavenly fruitdom, the book is available RIGHT NOW from me, signed, through my website, listed at right.

Wednesday, February 8, 2012

The first sign that spring is around the corner -- well, perhaps around the block -- is the aphids clustering on lettuce leaves in the greenhouse. For organically-grown lettuce, eradication of these pests isn’t reasonably feasible or probably even possible. So I try to strike a balance: As long as aphid populations don’t get too high, plants suffer but little. It’s also a balance between my tolerance for having to wash lettuce leaves to rid them of aphids and the number of aphids  I would tolerate eating. (They’re really not that noticeable or bad to eat; sort of tasty, in fact.)
You know those ladybugs that appear on the insides of south-facing windows this time of year? They used to be my first line of defense against aphids. I would vacuum them up with my Dustbuster, which made the ladybugs dizzy but otherwise caused little harm, and then sprinkle the stunned bugs around the greenhouse in late afternoon or early evening. Next morning, as temperatures warmed in the greenhouse, the ladybugs would go to work like little tractors, methodically crawling up and down leaves gobbling up aphids.
The problem is that the ladybugs can’t get past the new windows I installed a year ago in my house. But no need to resort to pesticides. 
A blast of water from the hose in the greenhouse is sufficient to knock many aphids off the leaves. It’s important to get both sides of the leaves. And it is important to keep up with burgeoning populations. Aphids are amazingly fecund, under ideal conditions their populations doubling every couple of days. They reproduce by mating, like most other animals, and also by parthenocarpy, that is, without mating. Sometimes they lay eggs and sometimes they give birth to live young. I’ll also keep an eye on other greenery in the greenhouse because a single aphid species can attack many different host plants.
Natural controls, including other insects, rain, and cold, help keep aphid problems in check. But natural controls are not as effective in the greenhouse as outdoors, where I rarely encounter aphid problems worth bothering about. So I’ll be regularly blasting the greenhouse plants with water in the coming months. And, no doubt, eating some aphids.
Staghorn fern is among my weirdest houseplants, especially as it grows larger and larger. About 1990, I bought the plant, a cute little thing in a 3 inch flowerpot. I also bought a softball-sized chunk of tree fern fibre on which to grow this normally epiphytic plants. The plant went into a hole gouged into the fibre, then was held in place with wrappings of fishing line. An eyebolt screwed into the fibre offered a convenient way to hang the plant.
Staghorn fern grows two kinds of fronds. The fertile fronds are green and are the ones that resemble stag horns in shape. Infertile fronds are tan and hug the soil, tree fern fibre, or -- the usual support for an epiphyte -- organic duff accumulated in the crotch of a tree.
Over the course of the 20 some odd years the plant has called that fibre block home, it’s grown many fertile and infertile fronds. The infertile fronds have totally enveloped the fibre block  to hide it, and the fertile fronds now appear at various places around the tawny mass. 
Most growth is in summer, when seedlings of other plants, including cedar trees and other kinds of ferns, sometimes take root in the moist mass. In winter, when the plant is indoors and hardly ever watered, these interlopers usually die off. The staghorn fern tolerates some drying out in winter, which is a good thing because watering it entails putting it in the bathtub and then giving it a shower long enough to let the water penetrate through all the layers of sterile fronds to wet the tree fern fibre. I let the plant set a couple of hours to let excess water drain away, then return it, now weighing about 10 pounds, to its east-facing window.
The wild fern interloper that established itself in some crevice in the sterile staghorn ferns last summer seems to be thriving along with the staghorn fern this winter, which should make for an even more interesting hanging plant in years to come.
Today is a big day, the first seed sowing of the 2012 gardening season. Lettuce and onions. The lettuce for the greenhouse. The onions for eventual transplanting outdoors.
Some of the lettuce seeds will go right into the ground in the greenhouse and some of the seeds will be sown in seed flats for later transplanting in the greenhouse. The seeds sprout sooner in seed flats but the plants are more resilient, less apt to dry out or go to seed, when started right in the ground.
The plan is for these new lettuce plants to come into their own just as the last of last autumn’s lettuce plantings are harvested.

Thursday, February 2, 2012

At almost a year old, my bonsai is looking, if not wizened, at least tree-like and a welcome sight in winter. This bonsai began life in a big box store, a weeping fig in a 4 inch pot. Weeping figs are so easy to root from cuttings that the propagators of these plants evidently don’t even bother with individual cuttings, instead just sticking clumps of them together. Or maybe they’re sold in clumps to make the plants look bushier. At any rate, I divided the clump as soon as I got home and then had 4 weeping figs.
In the tropics, I’ve seen weeping figs as large as our sugar maples. In large pots indoors, I’ve seen -- and once had -- weeping figs 6 feet high. I planned for one of my new weeping figs to call home a rectangular pot 1 inch deep by 6 by 4 inches long and wide -- for its whole life! Another of the weeping figs was destined for a round pot just a bit over 2 inches wide and deep, also for life.
To fit these small plants into even smaller pots, each got its roots and tops clipped back, the roots for a good fit into its future pot and the tops to balance root loss and to give the “tree” an attractive form. All this began last summer, and the plants spent a few weeks in light shade to recover from the butchering.
Once recovered, the plants began to grow, which is good and bad. Growth is needed to keep any plant alive but the goal was, and is, to keep the plants small and in proportion to the dimensions of their pots, all the time maintaining good form, of course. One way to keep a plant small is to periodically cut back shoots. Another way to keep a plant small is to periodically cut off its leaves. As I wrote in my book, The Pruning Book, “Timed correctly . . . leaf pruning forces a second flush of leaves that are smaller and hence better proportioned to the size of the plant.” 
I also wrote that “leaf pruning is not for every bonsai. Do not do it to evergreens . . .” Weeping fig is evergreen. Oh well, I’m going to try it anyway.
This is the bonsai last summer, after I snipped off all its leaves.
As the plants age and their trunks thicken, I’ll help them along on their way to wizened gnarliness, creating dead stubs, gouging out wood where branches are removed, and, if necessary, using temporary wires to direct branches.
Plants need to be healthy to tolerate such treatments. In a few weeks, and every late winter or spring thereafter, I’ll tip the plants out of their pots, cut back some roots, and then snuggle the roots back into the pot refreshed with new potting soil. Branches also will get pruned at least yearly for health and beauty. 
I hope these trees thrive not only for my viewing pleasure but also because I devoted a whole chapter to bonsai in The Pruning Book. (This book also covers other special pruning techniques, such as espalier and pollarding, as well as standard pruning techniques for all kinds of plants.)
It doesn’t seem premature to state that I’ve failed again: Three jasmine plants are, once again, all leaf and no flowers. Jasmine (Jasminium polyanthum) is a plant that is easy to grow and easy to propagate; hence all the greenery and the number of plants I’ve had over the years.
The main reason to grow jasmine, though, is for the sweet perfume with which it fills the air when in bloom. At least I think it’s a sweet perfume because I can hardly remember the aroma. I got the original plant 11 years ago and remember how proud I was getting it to rebloom for the first couple of winters.
So what makes your typical tropical or subtropical winter blooming plants -- Christmas cactii, poinsettias, amaryllises, and the like --  bloom when they do, or at all? A period of cool temperatures, short days (long nights, actually), or dryish conditions. Any or all of these changes for a period of time in autumn triggers flower buds for winter. 
My three jasmine plants have received the requisite treatments yet, as I stare at the plants, I see no hint of a flower. Just lanky stems grabbing at other plants or sprawling on the floor.
A friend suggested that my jasmines have grown old. They did all originate as cuttings from my original plant of 11 years ago. It’s not a good explanation but the only one left. I’m buying a new plant.
No, I’ve decided not to buy a new jasmine plant. I’ll give my plants one more chance (as I have every year for the past 9 years). White Flower Farm nursery, which has sold jasmines for years, offers some more exacting instructions on growing the plants: “Prune as necessary to control size or to maintain shape, but stop pruning by August 1, because the plant sets flower buds in late summer. To encourage the formation of flower buds for next winter, be sure your plant experiences the cooler temperatures and shorter days of early autumn. The plant needs 4-5 weeks of nighttime temperatures between 40° and 50°F, plenty of sunlight, and the complete absence of artificial light after sundown. Bring the plant indoors before frost. Then give it cool temperatures [below 65°] and indirect [but bright] light until it blooms again in late winter.”  I will follow these instructions to the letter. Wish me luck.
Last post I mentioned battling scale insects on house plants with sprays of horticultural oil in autumn. A reader wrote to offer another remedy: soap sprays. I’ve also used soap at various times, and it is effective, especially specially formulated “insecticidal soaps.” You do have to be a little careful because some soaps at some concentrations can damage some plants. (That’s a lot of “somes.”) The reader mentioned the especially environmentally friendly tack of saving shower water in a bucket, which, the reader wrote, results in a perfect soap concentration for insect control. Whatever works.