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The Season Begins

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One More Thing? Ha!

I have one more important task to do before planting any vegetables this spring, and that is the annual mapping out of the garden, something I generally put off as long as possible.

In theory, mapping out my garden should be easy. I “rotate” what I plant in each bed so that no vegetable, or any of its relatives, grows in a given bed more frequently than every 3 years. Garden planning on paperIn practice, I mostly pay attention to rotation of plants most susceptible to diseases, which are cabbage and its kin (all in the Brassicaceae), cucumber and its kin (Cucurbitaceae), tomato and its kin (Solanaceae), beans and peas (Fabaceae), and corn (sweet or pop, in the Gramineae).

Crop rotation prevents buildup of disease pests that overwinter in the ground; removing host plants eventually starves them out. (Insect pest are more mobile, so crop rotation has less impact except in very large plantings.) So one year a bed might be home to cucumbers, melons or squashes. The next year that bed might host cabbage, broccoli, kale, Brussels sprouts, or cauliflower. Then tomatoes, peppers, potatoes, or eggplants. And finally, the fourth year, back to cucumbers. Simple enough.

It would also be nice to rotate carrots and other root vegetables with leafy vegetables, such as lettuce, and fruiting vegetables, such as tomatoes. My garden's bedsRoot, leafy, and fruiting vegetables have somewhat different nutrient needs, so in the ideal garden these crops are rotated to make best use of soil nutrients.

And I do like to get the most out of my garden and confuse potential insect pests by grouping different kinds of plants within a bed.

Are you beginning to understand why I put off committing my garden plan to paper each spring?

Pea Problem(s)

Peas present one more wrinkle in my vegetable garden planning. A few years ago they stopped bearing well, collapsing with yellowing foliage not long after they bore their first pods.

Further investigation has narrowed the problem to – probably – one of two diseases: fusarium or aphanomyces. Both, unfortunately, are long-lived in the soil so that a 3 year rotation does nothing to keep them in check.

Fortunately, I have two vegetable gardens. So, for the past few years I have banned peas from my north garden, planting them only in my south garden, in which they do get rotated. After a few more years, I’ll move the pea show to my north garden and leave my south garden pea-less. I’ve also been planting the varieties Green Arrow and Little Marvel, both of which are resistant to fusarium, at least.

Unfortunately, the problem is more likely aphanomyces, for which resistant varieties do not exist. Aphanomyces is a water mold, so thrives under wet conditions. So my tack will also be to keep any peas planted in my vegetable garden on the dry side, not even turning on the drip irrigation in those beds.

I’ll also be checking the plants more closely for symptoms. Plants infected by fusarium have a red discoloration to their roots. Fusarium-infected pea rootsPlants infected by aphanomyces have fewer branch roots and what roots there are lack the plump, white appearance of healthy roots.Pea roots with aphanomycesPea roots with aphanomyces

Pea Solution?

I’m also testing out root drenches with compost tea for my peas.

Yes, yes, I know I have dissed compost tea in the past. Mostly, its benefits, if any, have been overstated. But compost microbes have more chance of surviving in the dark, moist, nutrient-rich environment of the soil than on a leaf, where the stuff is often sprayed. I’m drenching the soil with the tea, not just giving the surface a spray, as usually recommended, so a lot more bacteria, fungi and friends are finding their way down there.

I see no reason (and research does not support) of going to the trouble of making the usual compost tea, which is aerated and might be fortified with such things as molasses. Compost tea, quick mixMy tea is nothing more than the liquid strained from compost soaked in water, then applied with a watering can at the base of the pea plants.

I’ve done this for a couple of seasons but have nothing definite to report yet. The hard part is sacrificing a bed as a control. Perhaps this year.

Graft, the Good Kind

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My friend Sara had a question about graft, which made me immediately think of a recent news item stating that, for the first time, more than half of the members of Congress are millionaires. You rarely hear about graft these days, perhaps because dollars are so ubiquitous a lubricant for our political machinery. No need anymore to elevate the practice with a special word.
But Sara was talking about grafting, not graft, and it was for tomatoes. Apples, peaches, and other fruit trees have been grafted for centuries. Tomato grafting is relatively recent, at least in this country. Sara wanted to know my thoughts about grafting tomatoes and whether we should pool our resources to get some plants.
Grafted tomatoes might grow more vigorously, might be resistant to soil-borne diseases, and/or might be more tolerant of salty, wet, or cold soils. A grafted plant has a specially chosen rootstock — Maxifort, Beaufort, and Emperador are some common ones — upon which is grafted a good-eating variety, often an

heirloom variety. Whether or not, and which, positive traits the resulting composite plant possesses depends on the choice of rootstock. Grafted plants have allowed farmers to keep growing tomatoes in greenhouses and soils where the plants would have otherwise petered out from nutrient problems or buildup of disease.

With decades of grafting fruit trees under my belt, I’d feel confident grafting tomatoes. There are a few differences, of course: tomatoes are grafted when small (with 2 to 4 leaves); they are succulent and in leaf so need to be kept in high humidity until the graft heals; and, best of all, you see results quickly, within a week or two. You start by sowing seed of the rootstock variety followed, a week later, by sowing the scion (eating) variety. Once rootstock and scion plants are large enough to graft, you lay their stems side by side and make an angled cut into both at the same time with a straight-edge razor. Set the bottom cut of the scion atop the top cut of the rootstock and then hold the stems aligned with a tomato grafting clip or piece of tape. After a week or so of warmth, high humidity, and indirect light, the graft should be healed and the composite plant ready to acclimate to brighter light, cooler temperatures, and lower humidity and — eventually — outdoor growing conditions.
An easier but more expensive route would be to purchase grafted tomato plants. Sources such as http://territorialseed.com and http://www.johnnyseeds.com sell grafted plants as well as rootstock seeds and grafting clips.
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Do I want to grow grafted tomatoes? Yes, I’d give the plants a try — if grafted plants of an heirloom variety landed in my lap. Which is to say that I’m not ready to spend much money or effort on grafted tomatoes.
One reason is vigor. Grafted tomatoes grow more vigorously, but my ungrafted, staked  tomatoes always start to grow out of reach by the end of August. More vigor? No thanks. Also, there’s often an inverse relationship between vigor and fruitfulness.
As far as diseases, I avoid planting tomatoes where they’ve grown for the past three years, clean up old stems, leaves, and fruit thoroughly at the end of the season, and mulch each year. In so doing, buildup of soil pests is avoided, overwintering inoculum at the beginning of each season is reduced, and spores of overlooked diseased tissue are buried.
When asking me about grafted tomatoes, Sara probably had in mind late blight disease, which has devastated tomatoes in recent years. Grafted tomatoes offer direct protection only against soil-borne diseases, such as verticillium and fusarium wilt. Around here, at least, early blight, septoria leaf spot, anthracnose, and late blight are what strip plants of leaves and pockmark the fruits. Grafted plants would not be resistant to these diseases.
Increased vigor might help a plant pump out extra fruits in spite of disease — or not. I’m not going to any special efforts to plant grafted tomatoes.
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Apples are another story, one for which I am turning to rootstocks and grafting.
First, a little background: I have an especially poor site for growing apples. Cold or cool, moist air collects in this low spot, making plants prone to disease and frost, and the 6,000 acres of woods fifty feet away provide haven for insect pests. The site is also wetter than I realized. Still, when I do get to harvest apples, their delectable flavor makes them worth the effort.
As with tomatoes, an apple rootstock can impart certain desirable characteristics to the resulting composite tree. My present planting is a row of superdwarf trees. These small trees, although early bearing and productive, need codling with perfect soil. My plan is to make new trees that are more tolerant of less-than-perfect soil conditions and, being taller, might hold their heads in slightly more buoyant air to reduce disease pressure.
Apple has been grown so widely and for so long that many rootstocks have been developed. Thus far in

A young pear graft

my research, a rootstock named G.30 seems the best option, creating a mostly self-supporting (except with certain varieties and heavy crop load when young), medium-sized tree tolerant to wet soil and fire blight disease. Best of all, it promotes of early bearing of the scion variety grafted on it.

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I’ll be lecturing at the NOFA-CT winter conference on March 1st in Danbury, CT. The topics? “Growing Figs in Cold Climates” and “Multi-Dimensional Vegetable Gardening/ Farming.”