Brown Rot Strikes Again

   The plan was for me to be now sinking my teeth into the soft, juicy, rich flesh of my Oullins golden gage plums. The tenuous start this past spring, with a freak late freeze that sent temperatures plummeting into the low teens, had me worried. The trees shook off the cold and, when warmer weather returned, burst into snowballs of white blossoms. Tiny fruitlets that followed those blossoms have swelled to the bountiful crop now dangling from the branches.
    The plan has been foiled — by brown rot disease. Almost every plum, just as its skin starts to shade towards ripeness, becomes spotted with fuzzy, gray droplets that, with good weather (good for the fungus, that is), soon covers the fruit.Brown rotted plum fruit
    Brown rot was not unexpected, and a counterattack was planned. All through spring, before blossoms even unfolded, I doused the plant with insecticide and fungicide sprays. Insecticides help control brown rot by preventing insects, most notably plum curculios, from laying eggs in the developing fruitlets. Even if the egg-laying itself doesn’t cause the fruit to drop, holes left behind provide easy entrance for the brown rot fungus.
    Perhaps I was too lenient, using relatively benign (to us humans, that is), organically approved sprays. ‘Surround’, a commercial formulation of kaolin clay for the insects. And sulfur, a naturally occurring mineral, for the brown rot fungus.Brown rot mummy
    That’s not all. Gathering up infected fruits cuts back the number of new disease spores that waft among the branches looking for new fruits to infect. In fall and winter, those infected fruits are easily recognized as blackened, dry “mummies.” They lose their dryness and come to life, fungal life, with spring’s warmth and moisture. I’ll gather them up also. I’m hoping my ducks develop a taste for the fresh, dropped, rotten fruit; so far, they seem to be picky eaters.
    My late winter pruning of the trees should also have helped reduce brown rot disease. Removing enough stems and limbs to allow those that remain to bathe in light and breezes allows for quicker drying from dew or rain.

The Disease Triangle

    Three conditions must be satisfied for any disease, whether in animals or plants, to take hold: inoculum must be present, the host must be susceptible, and the conditions must be suitable for disease development. Check, check, check for my Oulin plum (a susceptible host plant) getting brown rot here in the Hudson Valley, throughout most of the humid eastern U.S., in fact. We have plenty of wild and cultivated plums and related plants here to provide brown rot inoculum from infected fruits, and the weather is usually just about perfect (for the disease, that is).
    But Oullin isn’t the only great-tasting plum. How about a less susceptible host variety? Fungi are picky eaters, and varieties of plants vary in their susceptibility to specific diseases.(Unfortunately, most gage-type plums, which are heart-shaped, with greenish flesh, are very susceptible to brown rot.)Infected plums on tree
    My plum trees are grafted to multiple varieties. The variety Shiro also finds a home on the tree grafted to Oullin. This year, and in years past, Shiro seems to be somewhat resistant to this disease. And I see that Cummins Nursery has a variety called Jam Session that also is resistant. This past spring I also planted the varieties Alderman and Superior, which are American hybrids with some alleged resistance.
    As consolation, plums are, at least, less susceptible to this scourge than are peaches and apricots.

Flowers to the Rescue?

    I’m planning and planting for flowers for next season and for years to come, with perennials.
    I could, of course, just purchase some potted plants to plug into the ground now or next spring. I could buy seeds and sow them next spring. Instead of those two options, I’m sowing seeds now, a time when, admittedly, there’s not that frenzied urge to plant seeds as in spring.Black-eyed SusanPurple coneflower
    One packet of seeds can — should — result in oodles of plants, plenty to plant and to give away. Sown now, the seeds should grow into plants that will be large enough to weather autumn, then winter’s, cold. Plants should also be large enough to flower next year. Their experience of cold, known as vernalization, will further coax them on to flower. Spring sown perennial flower seeds often don’t flower their first season, no matter what their size, because they have yet to be vernalized.Liatris
    I’m sowing purple coneflower (Echinacea), black-eyed-susan (Rudbeckia), and blazing star (Liatris). They’re all in the daisy family, a family known not only for its good looks but also for providing nectar to attract and help support beneficial insects. If I plant enough, perhaps the increased number of beneficial insects will significantly decrease the number of plum curculios and other plum fruit insects resulting in, because of less insect scarring of fruit, significantly less brown rot of my plums.
    It’s a stretch but the flowers, anyway, are very pretty.


Don’t Go With the Gut

   “April showers bring May flowers.” Where? Not here. I had many years of gardening under my belt before I realized the falsity of that little ditty. Yes, it happens to be raining as I write these words at the end of April. But generally, April is dry, and todays’s rain amounted to a mere quarter-inch.
    For years, I would sow radishes, lettuce, arugula, and other early, cool season vegetables in April, and figure “April showers” would take care of watering needs. Which they did not. With frosts still likely around here, April was too early to get the drip irrigation going. So watering vegetable beds requires tedious lugging of hoses, making sure, as I pull on them, not to knock over plants or mess up carefully formed beds.
 Watering wand   Hand watering also required patience. A light sprinkling of the ground does nothing but wet the surface fraction of an inch. If you care to know, the amount of water needed to wet a soil about 6 inches deep is 3/4 of a gallon per square foot or, equivalently, a one-inch depth of water. And said water needs to be applied slowly enough to percolate into the ground rather than running off elsewhere.
    Fortunately, with cool temperatures and plant growth only just beginning, much of the moisture from previous months’ rain and snow still sits in the soil. The surface often looks dry while moisture is sufficient below. So all that’s needed is to keep the soil moist from the surface to a depth where the ground is still moist.


    Eyes or the gut are not reliable indicators of when to water. Sometimes I’ll just poke my finger into the ground to assess moisture level. But does it really feel wet, or does the soil feel cool because it’s April?
    All that’s needed are your hands for the more accurate “feel method” of soil moisture determination. For this method, you need to know your soil’s texture; that is, is the soil a sand, a loam, or a clay? Crumbling it, feeling its slickness, and attempting to form it into a ball or a ribbon gives some indication, depending on the texture, of moisture content (see for details).
    All sorts of high-tech soil moisture measuring devices are available: electrical resistance blocks, tensiometer, time domain reflectometer, neutron probe, and more, all beyond the wallet and accuracy required by of most gardeners.pH, moisture testor
    On the other hand, inexpensive soil moisture meters are readily available. What they lack in accuracy they make up for in convenience. Sliding the thin, metal rod into the ground gives a pretty good, qualitative measure of moisture anywhere from just below the surface to the length of the rod, which, depending on the device, is 8 to 12” inches long.
    Watering is an important key to success in gardening, and for $10 to $50, these relatively moisture meters are well worth the money. The more expensive, previously mentioned monitors can be left in the ground. The inexpensive meters must be removed and their probes cleaned after each measurement.

Indoor, April Showers Bring . . . Yes!

    Even if April showers do not bring May flowers, April — the month — does bring a few May flowers, but mostly flowers in June and beyond. That’s because April is the month when I sow many flowers for transplanting out into the garden after warm weather settles in. On the slate for this year are Lemon Gem marigold, sunflowers of all stripes, chamomile, moonflower, morning glory . . . (Where am I going to plant all these flowers? Spring’s got a hold on me.)

Tussler Was Correct After All

    The ditty “April showers bring May flowers” really does have some truth to it — if you’re in the UK, where the ditty originated. There, the northward moving jet stream picks up more and more moisture as it travels across the Atlantic Ocean; the result is rain by the time the winds reach the UK. (On this side of the “pond,” the jet stream, traveling across land, has picked up relatively little moisture.)
    So Thomas Tusser, who allegedly penned “Sweet April showers / Do spring May flowers” in the 16th century (in A Hundred Good Points of Husbandry), was not wrong, for Great Britain. Here, we have to water in April. But not too much.