Vermont Vegetable and Berry News – March 14, 2007
Compiled by Vern Grubinger, University of Vermont Extension
(802) 257-7967 ext.13,


(East Montpelier) It’s been cold here but the greenhouse has done really well this winter. I stopped harvesting greens, spinach, and carrots at the end of January, to take a planning break. Last couple of weeks the sun has really jump-started things in there. Have plenty of onions going and flats of early head lettuce and cabbage. I’m trying transplanting of sugarsnap peas into the greenhouse and under row cover, after the cold breaks a bit. I also seeded 5 beds of sugarsnaps in December and these are sprouting out, also under row cover - seems promising. Had some trouble with fungus and excess moisture in the greens this winter. Waiting to see if I have another early attack of flea beetles in my greenhouse spinach. Last year they spoiled one early spring cutting then went away and everything came back fine. I’m using row cover to see if I get protection from them.

(Dummerston) The big freeze has subsided, the propane is flowing freely to the outer greenhouses and we've been able to sleep the whole night without cranking up the auxiliary heaters. It’s hard to raise a greenhouse temperature 70 degrees, from 10 below to 60 above. Grafted tomato plants are almost ready to blossom so it’s time to get them planted for red fruit in May. Also need to Zerotol the empty greenhouses and check cuttings for signs of overwintering thrips. Kill one now, save a lot of trouble later. Overwintered spinach under plastic is coming back to life so we should be able to cut it a couple of times before tilling for next crop. Maybe squeeze in a planting of beet greens before tunnel tomatoes take up residence in late April. Now's also the time to plan advertising, fill in the NOFA application, wrap up taxes, and check the pH meter before things get crazy - which in my limited experience, always happens sooner than you think. So put a bookmark in the novel for next fall and unplug the TV: it's showtime.

(Londonderry) I had a long run of greens this winter. My last harvest was January 10th of arugula, mustards and Asian hearty types.  I only heated 10 days from mid-August to January! Now the deep snow insulates all sides of houses and tunnels. Most are still full of empty benches and hoses and stuff. Only days until the old row covers are unfolded and moved to a new location to for the growing season. I am digging out from 3-plus feet of snow in about ten days and getting more then ready to see some green! We plant more seeds next week.

(Plainfield NH) Last week’s cold weather was stressful on many fronts, straining greenhouse heaters to their max at night and making ventilation tricky during the day. I have some nice purplish tomato seedlings and frost-bitten fingers to show for it. Otherwise, the onions are popping up and lots of rooted cuttings to pot up. After a mostly snowless winter we were able to get enough cover for protection of small fruit in last week’s arctic blast. Trying to finish up a barn and get some machinery repaired before it gets really crazy around here...

(Shaftsbury) Finally committed to starting up greenhouses after the cold nights. We are installing two more Bartlett computerized greenhouse controllers in greenhouses this year. Last year we put one in a house that was always damp and never seemed to grow as nice plants as we liked, and the plants were perfect! With the Bartlett you can have different day and night temp settings, and there is also a "Dif" setting where you can drop temps just before daybreak. It also has a humidistat and it will vent/heat to control the humidity. The new ones will go in a tomato house and one in another bedding plant house. Each controller will do 2 houses if you want, but they have to have the same temp requirements. At $750 including humidistat they are well worth it.

(West Rutland) Well, it is time again to ring forth the year with glad tidings, after shoveling snow off the greenhouses, shoveling snow off the wood piles, etc. Shoveling makes me think back to the old dairy days when we had no gutter cleaner. The good news is I will be starting this weekend and missed the below-zero heating nights for the moment. And for all those who thought I was nuts by burning wood to heat greenhouses, how crazy am I now you petrol abusers.

(New London NH) Our ‘Micro-Mix’ has a small but steady following throughout the winter with three local restaurants and 3 local "junkies" buying up most of our harvest every week. Wish we could find more accounts since we are making the effort. The mix is very slow growing through November, December and January. Once February hits, the mix grows more quickly and turns on the bench become more affordable. We started up two greenhouses with a third and fourth due on line next week. Seed germination is good so far, as are the purchased plugs and liners. Hoping for some labor efficiencies with a new plug puncher transplanter we just bought. Our farmstand opens April 2nd. Hope some of this snow melts by then.

(Durham CT) We have three heroes this winter: red Russian kale, claytonia and spinach (variety: Space).  Of all our winter greens, these three are the sturdiest. They were all planted in late October and became large enough by early January to harvest.  Because of this we have been selling greens all winter. The spring crop is 90% planted with an expectation of being ready to harvest by the beginning of April. Our first planting of tomatoes (there are three) are in soil blocks, about 4 inches high.

(adapted from Jeff Kindhart and Tony Bratsch, Univ. of Illinois, via UMass Berry News)

A common sign that mulch should be removed is the presence of new growth. Many growers delay mulch removal in an attempt to delay flowering time and avoid frost damage. Unfortunately, this delay has little effect on flowering time and may result in reduced yields. The best way to gauge the timing of straw removal is by monitoring soil temperature. Most strawberry roots are found in the top 8 inches of soil, so taking soil temperature at a depth of about 4 to 5 inches is recommended. In a Univ. of Illinois study, mulch removal timing was evaluated at soil temperatures of 38, 43, 48 and 54 degrees F. The time when soil held steady at these temperatures for at least 3 days was roughly mid March, late March, mid April and late April (at this particular location.) Mulch was removed at these times, over a range of five weeks. The greatest yields were obtained if mulch was removed when soil temperature was 40 to 43 degrees F. The research also found that even between the earliest and latest dates of mulch removal, early bloom was separated by only 11 days and first harvest by only 3 days. Thus, the advantage of early mulch removal to promote early maturity was minimal. However, production was shown to increase by early removal. Late mulch removal actually decreased yields, mainly due to leaf etiolation (elongation under shade conditions) and reduction of leaf area due to sunburning. Some crowns were also killed by a delay in straw removal.


I continue to see growers using the standard ‘field’ soil test for their high tunnels and greenhouses. In most cases the results are typically interpreted as ‘off the charts’ because this test is intended for open field situations where required available nutrient levels are lower since growing conditions are slower, so to speak. It is much more informative to use the ‘saturated media’ test or potting soil test where greenhouse crops will be grown in highly fertile mixes of soil and compost. This test also gives you more information than the field test: besides major and minor nutrient levels, it reports soluble salt level (conductivity) and available nitrogen (nitrate and ammonium). The test costs $25 and requires a full cup of soil. Send to UVM Ag Testing Lab, Hills Building, Carrigan Drive, Burlington VT 05405-0082. UMass also offers the test (and for just $10), the form is at:    In either case, include your contact information, greenhouse name and crop type. Results can be e-mailed to you; ask that a copy be sent to me if you want recommendations.


Initial Certification Exam Training for those wishing to obtain a Vermont pesticide applicator's license will be held on April 11 at the 3 Stallion Inn in Randolph, from 9am to 5pm.  Coffee, pastries and lunch are included in the registration fee of $40.00. The exam will be given from 2 to 5pm, immediately following the training. Bring a calculator. For a link to the brochure go to For more information contact Ann Hazelrigg, Univ. of Vermont Extension at (802) 656-0493 or

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