Vermont Vegetable and Berry News – April 11, 2007
Compiled by Vern Grubinger, University of Vermont Extension
(802) 257-7967 ext.13,


(Westminster West) Here the report from the field is snow. Before the 4 to 5 inches we got last week I did see the garlic up a couple of inches. The snapping turtles are getting ready for their annual visit to the nice tilled, soft warm soil of our fields to lay their eggs again. Anyone else have snappers as a crop pest? They don't eat anything, but their egg-laying action damages young transplants. I’ve been selling ‘Mudseason mix’ salad mix to the food co-op for a couple of weeks. It’s grown in a hoophouse, unheated, in the ground. Tatsoi went to seed quickly because of the cold, as usual. The spinach and pak choi grown in trays have been delicious! The cold, cloudy April has been sucking a lot of propane for the greenhouse seedlings. And a two-hour power outage had us concerned for the young tomato plants down there. Looking forward to the beginning of warm Spring

(Westfield) Hopefully we harvested the last crop of snow (one foot); we had a good yield of that this year. On the green side, we’re in the second week of picking overwintered spinach in the unheated greenhouse. Bedding plants are doing fine and last week of March I transplanted the greenhouse tomatoes. I used Jake Guest’s idea that he presented at the VT Vegetable and Berry Grower’s annual meeting about using clear plastic to warm up the soil quickly. After just 6 days the soil was at 70 degrees in the middle and 60 degrees at the end of the house. Usually I have 60 and 45 degrees at this time and have to wait 10 to 15 days to have the end row up to 60 degrees.

(S. Royalton) Beets, carrots, radishes, spinach, lettuce all up and growing very sloooowly under our sunless skies in the hoop house.  I've got every inch of floor space covered.  Just starting to think about moving my vegetable starts from under the lights in the basement into the greenhouse.

(Cambridge) We sent out ads for our CSA this season, and the responses are steadily flowing in. The three greenhouses are now all running. One is full of hanging baskets and blooming pansies and six-packs. Peppers, eggplants, and celery are about 2 inches tall. Onions are about 5 inches tall. Most herbs basil, parsley, and thyme are up and waiting to be transplanted.  Geraniums from seed are 2 inches high in 4 inch pots. The first tomatoes are planted and the grafted tomatoes will be planted this week. A European-type cuke will also go into the greenhouse this week as they are starting their tendrils. We are not in the field yet but anxiously waiting.  I peeked under the mulch and saw some spinach starting to green-up. About 30 of the chickens have begun laying at 5 months old.
(Killington) The garage wall is full of seedlings under fluorescent lights waiting to go into the hoop house where the thermostat is set at 60 degrees to accommodate 200 tomato plants. I hope the propane doesn't break me! There will be price increases this year on the vegetables and the price of grain will drive up the cost of eggs, pork and beef....and there's no inflation?

(W. Rutland) Plants are growing well even though we are lacking sunshine. A friend of mine said he saw a magazine headline that said "forget organic, by local". I could not agree more.

(Amherst MA) A cold start here as we haven't been able to do anything in the field, which is still frozen in the mornings. We did try taking some straw mulch off the strawberries, just to get something done out there, but it was so cold, and the forecast didn't look promising so we stopped. Working on machinery (with cold hands), in the greenhouse (all caught up), fencing of permanent pastures, and construction projects (when we have some room inside). Supposed to start seeding in the field this week - we'll see if we can get the plow into the ground.

(Little Compton RI) An oil furnace literally blew up this week! Our transformer was putting out an intermittent 5000 volts instead of a steady 10,000+. We found it shut down and hit the re-set button and everything sounded good but there was a pool of oil inside heating up. About two minutes later it all vaporized and boom: split the chimney and the boiler right open! Lucky we were in a nearby house because the furnace kept right on running! The bottom line: have your repair guy check the volts on all transformers over two years old. They must do it with the correct piece of equipment; a screw driver across the springs doesn't cut it. In fact doing the screwdriver trick can ruin them real quick. The greenhouse tomatoes didn't like the smoke one bit. They all were hanging over like they were dead. Luckily they are now well on the way to recovery. We have been using Oxidate for green algae control in our onions this year with good success. It is important to do the treatment right from the start with a1:300 solution. If you wait until you have a thick matt of green it is too late so don't bother trying. Be sure to wear disposable gloves the Oxidate will eat your skin! We will be trying clear plastic on our cucumbers and melons this year. We have heard the arguments and it makes enough sense to give it a try.

(Durham CT) The late winter greens that I planted last Feb 15 are the best and largest of the lot. That might be because of better light or an extra amount of peat in that house. Our first crop of spinach planted in a high tunnel Feb 4 is ready. We have enough variety of greens for our first farm market on April 21. The micro-greens have been coming in strong for over two weeks. 500 tomato plants in so far. A small attack of cutworms in one area was overcome by an application of spinosad.  We're determined not to run out of Sungolds this year. In the low tunnels outside, the salad greens are doing great. There was a small window of opportunity before the cold, where I could work outside easily. The other factors for being able to work the soil outside early are raised beds and compost.

(adapted from UMass Extension)

A key to suppressing foliar disease in the greenhouse is to keep the plant canopy dry, especially from dusk to dawn. This is accomplished through proper watering and adequate plant spacing, having well-drained floors, warming plants, moving air and venting moisture. The least expensive method is to keep the greenhouse dry, especially going into the night, when the temperature drops. Puddles on the floor and water on leaf and media surfaces evaporate and add moisture to the greenhouse, which creates humidity, and that takes away energy that is intended to keep a house warm. Water your plants just enough to prevent excess water on the floor, and water early enough in the day so plant surfaces can dry before evening. The highest relative humidity in a greenhouse is in the plant canopies, where moisture from transpiration gets trapped due to insufficient air movement. Adequate plant spacing and mesh benches will help to improve air circulation at the plant level. Remove weeds as they also contribute to high humidity.

Bottom heat will improve air circulation inside plant canopies and helps prevent condensation on leaf surfaces. As warm air rises it creates air movement around the plants, and it keeps plant surfaces warm, preventing condensation on them. Combining heating with ventilation is important for reducing humidity. Ventilation exchanges moist greenhouse air with drier outside air. Heating brings the outside air up to optimum growing temperature, and it increases the capacity of the air to carry moisture, avoiding condensation. Neither practice alone is as efficient as both combined.

To vent humid air in greenhouses with vents, the heat should be turned on and the vents cracked open an inch or so. When doing this the warmed air will hold more moisture (RH), escape from the greenhouse through the vents, and be replaced with outside air of lower RH. This natural rising of the air will result in a greenhouse of lower relative humidity. In houses with fans, they should be activated and operated for a few minutes and than the heater turned on to bring the air temperature up. The fans should then be shut off. A clock could be set to activate the fans. A relay may be needed to lock out the furnace or boiler until the fans shut off so that both the fans and heating system do not operate at the same time and flue gases are not drawn into the greenhouse.

The venting and heating cycle should be done two or three times per hour during the evening after the sun goes down and early in the morning at sunrise. The time it takes to exchange one volume of air depends on whether or not fans are used and the size of the fans and vents. For some greenhouses it may take only 2 to 3 minutes for air exchange. If using natural ventilation, it may take 30 minutes or longer. Heating and venting can be effective even if it is cool and raining outside. Air at 50 degrees F and 100% RH (raining) contains only half as much moisture as the greenhouse air at 70 degrees F and 95% RH.


The Capital City Farmers Market needs a vegetable grower to fill a key spot at this season's market while a long-time vendor takes a one year leave. If interested, an immediate response is needed!  Please email a letter describing the size and scope of your operation and what you would like to offer to: For more info, call Jessie Schmidt, at 685-4360.

Mention of pesticides is for information purposes only. No endorsement is intended nor is discrimination against products not mentioned. Always read and follow the label.