Vermont Vegetable and Berry News - May 1, 2005
Compiled by Vern Grubinger  vernon.grubinger@uvm.edu
University of Vermont Extension
(802) 257-7967 ext.13
http://www.uvm.edu/vtvegandberry

REPORTS FROM THE FIELD

(S. Royalton) Beets, radishes, mesclun and spinach are all showing themselves in the field. I got all my field work done during the dry season.  I tilled the rye in early this year and am glad for it.  It has been my number one spring weed when I let it get bigger.  Spinach did not survive the winter for the first time in years.

(W. Rutland)  Plowing is done, plastic laid, and the first beets, cabbage and broccoli are all transplanted. Garlic looks super and I have implemented the finest wildlife IPM program ever; I have seen not a track of any pest in any field to date.

(Shaftsbury) Peas are up, but greens are sitting in cool ground yet to arise. Finding a few aphids in ornamental greenhouses plus a thrips or two. Using Rhapsody for prevention on verbena in baskets and no powdery mildew so far (say Ďjinxí). Greenhouse tomatoes apparently have too much foliage and we are experimenting with leaf removal strategies to reduce their vigor. Great crew this year making it all happen.

(Jericho) Although it has been wet recently, we have been able to get into the field. There have been enough breaks to allow us to plant some direct seed crops, and prep the ground for planting this coming week. Greenhouse and hoophouse crops look good. Let's hope for some sunny weather this week!

(Norwich) Looks like a re-run of last year's wetness! First spinach planting is up and looks good but over-wintered planting is pretty spotty. Early green-sprouted spuds were put in on April 20 and covered but not doing much. Plastic-plug-covered Eros berries are at 20 percent bloom already which could be tricky with a frost, but others are not so far along. Thereís a very heavy cutworm population in first year plastic berries; so I uncovered and sprayed Bt on April 21. Early corn ground is ready to plant if it warms up. Greenhouse tomatoes are at fifth truss and look good, but I only have one hive and word is that hives are nearly impossible to get now. I got word that berry plugs from Quebec must be ordered NOW if needed for late summer planting.

(Starksboro)  Field work is on schedule and we had a good opening day of plant sales, so I'm optimistic. We decided a little late in the game to have a CSA here this year for the first time. A nearby farm had one for the last few years and they decided not to continue with it. I became aware that people who live very near us were looking far afield for a CSA to join rather than just shop at our farm stand. It seems the overall CSA experience is very compelling. We're very excited about adding the CSA to our marketing mix.

(Plainfield) My family insisted that I take down our dank, crumbling, wood frame greenhouse, and we are just about to cover a shiny new 30 by 48 gothic hoop house. Itís very exciting; lots of plants looking to move in right away. Peas are just showing their first spikes, hope to put in another planting this week in a gravelly field. First kale and chard transplants are out. Hope to get started on transplanting onions and leeks this week. Have to get going on some marketing efforts for my spring plant sale.  Strawberries look great coming out from under the mulch. Good new growth in this cool showery weather. Need to fill in the mulch and do a quick weeding. Just starting our winter squash plugs, don't want them ready before the weather is right.

(Stamford VT)  Too much rain over the past week. Peppers and eggplants were started back on March 30th. Tomato plants about a week later. Squash and cuke transplants will get seeded this week. A new selection of painted gourd birdhouses are ready for Mother's day sales. Expanding on cut flowers, heirloom tomato and eggplant selections this year and also adding different varieties of winter squashes.

(Argyle NY) Wet soils delayed our first plantings until April 9, then dry weather caused us to set up irrigation! The recent rains have been pretty good for watering in onion, lettuce and spinach transplants. First seedings are up and looking good of beets, carrots, spinach, dill, turnips, radishes and peas. Potatoes are just breaking ground.  Seems to be lots of flea beetles; our first ever purchased lady bugs are doing a great job on aphids on overwintered spinach. Our new greenhouse with radiant heat benches has been wonderful but giving us a few challenges for learning something new. Anyone else using bottom heat?  Our farmers' markets start this week. Off to another fun season!

EARLY SEASON PEST ALERTS

Flea beetles are or will soon be out and about: make sure that early brassicas are covered with row cover, or have some other means of protection. Hungry flea beetles can scoot under, around and through the tiniest holes imaginable, so make sure that all edges are well sealed with soil.

Cabbage root maggot fly activity begins with emergence of adult flies from their winter puparia in the soil. This has been shown to coincide with full bloom of forsythia. So far cooler weather has slowed both plants and insects down. However, watch for eggs on early brassica transplants (tiny, oblong white eggs laid in soil at the base of the stem). You can avoid maggot damage by delaying planting date or by using floating row cover.

Seed corn maggot damage is most likely during cold, wet springs similar to our current weather. Fields that are near woods and soils that are rich in organic matter are more likely to have maggot problems than fields greater than ½ mile away from woods, or those with sandy soils. To prevent damage, promote rapid germination and growth by planting as shallow as practical. Plow heavily manured or cover-cropped land early, so it will be less attractive to the egg-laying flies. Thoroughly mix in organic matter when preparing the soil and allow the soil surface to dry because the insect is attracted to decaying residues and moisture. When possible, delay planting until the first generation is pupating (probably early June). Seed treatments are available against seed corn maggots (see the New England Extension Vegetable Management Guide)

Cutworms can be deterred by cultivating fields in the spring after vegetation has appeared and grown a few inches, then delaying seeding to starve the cutworms. Plan your rotations to avoid row crops following a grassy sod. Plow sod fields in late summer or early fall the year before planting. Cultivate young crops frequently to injure and expose hiding cutworms to predators. Insecticide treatments can be directed toward the soil surface on the plants (see the Vegetable Management Guide).  Some growers report some control by mixing a concentrated Bt solution with bran and molasses and making patties of the material and placing them along the crop rows.

Chlorosis in early sweet corn may result from cold temperatures, which can cause leaves to appear yellow or light green in color, either uniformly or in a mottled pattern. Corn cannot make chlorophyll when the temperature fails to climb above 65 to 70 degree F for an extended period. Herbicides are not responsible for the problem. Varietal differences to cold tolerance exist. The corn will turn green when the weather turns warm.
 
Pavement ants have been reported in a Maryland greenhouse. The small yellow colored ants invaded hanging baskets and were feeding on the roots of petunias. The injury was so heavy that the root system was girdled and the plants collapsed. These ants were introduced from Europe and are common on the Atlantic coast. They are reported to damage several species of plants and also feed on plant seeds. Destroy infested plants.

POWDERY MILDEW ON GREENHOUSE TOMATO
(adapted from CT Ag Experiment Station)

The pathogen Oidium lycopersicum is relatively new to the Northeast and is not the same one that causes other powdery mildews that have been around quite a while. This year it has already been a serious problem in at least one greenhouse operation Iím aware of.

Symptoms first appear as light green to bright yellow spots on the upper surface of the leaf. The spots become more noticeable as they develop the typical white, powdery appearance. Powdery mildew of tomato is more aggressive than other mildews and once leaves are infected, they quickly turn brown and shrivel on the plant. The fungus spreads easily as abundant powdery spores are carried by air currents or production activities. Conditions that favor the disease are common in the greenhouse: high humidity and warm temperature, but unlike most other fungal diseases, water on leaf surfaces is not necessary for infection. Other hosts include rosemary, pepper, eggplant, and many bedding plant and weed hosts.

To prevent this disease do not grow bedding plants or ornamentals in the tomato house. Use adequate spacing between tomato plants to allow good air circulation. Maintain relative humidity below 90% using well-timed heating and venting. Scout regularly to identify outbreaks before they can spread. Diseased tissue should be removed as soon as itís detected by placing it in a plastic bag Ė do not carry infected material through the house. Production areas should be thoroughly cleaned and all plant debris removed between crop cycles. Control weeds in and around the greenhouse. If you have this problem, avoid susceptible cultivars in the near future, including Caruso, Match, or Trust.

To be effective, organic or conventional sprays should be applied as soon as symptoms are first observed since early control is critical. Be sure to get complete leaf coverage. Among the compounds registered for use in most states are chlorothalonil, paraffinic oils, bicarbonates, cupric hydroxide, sulfur, and Ampelomyces quisqualis (a biocontrol).

ĎJUST SAY NOí TO WORKING WET SOIL
(adapted from Cornell Washington County ag news)

Resist the temptation to till any field while it is still too wet. Plowing, chiseling, discing, rotovating, or other tillage of wet soils will likely cause compaction and hurt your yields this year and in the future. Dig down to the depth of tillage or at least six inches and crush some soil in your hand. If it crumbles, it is dry enough for tillage and tire traffic. If it clumps and mashes, it is too wet and you will harm the soil structure if you work the soil.

DOWNY MILDEW IS COMING
(adapted from Rutgers Extension)

Many vegetable growers on the east coast had problems with this disease last year, and it is already causing problems on cucurbit crops in the south, where it originates each year. Growers and scouts report that downy mildew is widely present and a major problem on cucumber, cantaloupe and squash around Southwest Florida and note that it has become a very aggressive and hard to control disease this season. The good news for us is that the disease takes some time to make its way north, so there is time to plan for it. Last year downy mildew was diagnosed in NJ the last week of June, and appeared in New England several weeks after that. This year itís not if it will show up but when, and right now no one knows. North Carolina State Univ. tracks the development of downy mildew from Florida to Maine and posts its whereabouts and the direction itís heading on the Cucurbit Downy Mildew Forecast website: www.ces.ncsu.edu/depts/pp/cucurbit/

SWEET CORN GROWERS NEEDED FOR PEST NETWORK

If you are you a sweet corn grower who uses pheromone traps to monitor flights of European corn borer, corn earworm, or armyworm moths, consider becoming part of the regional pest reporting network managed by the UMass vegetable program. They are looking for growers who would like to contribute weekly trap counts to the regional network of sweet corn pest information. Some trapping costs may be covered. Contact Ruth Hazzard at 413-545-3696.

CONGRATULATIONS WILL AND JUDY STEVENS

In recognition of two decades of stewardship, connection to their community, and production of healthy food, Golden Russet Farm has been named the 2004 Vermont Sustainable Agriculture Farm of the Year. The award will be presented at the farm on May 16th at 10 a.m. by Governor Jim Douglas, and you are invited. Call 802-656-5459 for directions.

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