Gardeners Exchange Group Meeting: 18 April 2015
Location: WVU Kearneysville Tree Fruit Research and Education Center
Topic: Growing Season Extension Using Row Covers/Tunnels, Soil Testing and Tool Care
Submitted by Julie Neely
It was a beautiful sunny day with over seventy people attending the lectures and demonstrations presented by Michael Harmon, Extension Agent, and Dr. Lewis Jett, West Virginia University Commercial Horticulture Extension Specialist.
Soil sampling really needs to be done at least annually to correctly replace nutrients used by your vegetable plants during the growing season. Crop rotation is beneficial to extending the growing capacity of your garden soil but does not replace soil testing and amendment with appropriate nutrients to replace depleted soil components.
Even if you regularly amend your garden soil with compost, soil testing should be done. Some nutrients can be harmful if they are present in too large of quantities. For example, high Calcium can bind up other nutrients making them inaccessible to your plants. Different vegetation requires and depletes different amounts of N (Nitrogen), P (Phosphorus), K (Potassium), Mg (Magnesium) and Ca (calcium) to name just a few. Some plants are heavy feeders, like tomatoes, and some are not. Some plants have different soil pH requirements. Most plants prefer a pH around 6.5 (slightly acid, pH of 7 is neutral). Blueberries, azaleas and rhododendrons prefer more acidic soil conditions (lower pH). If you add powdered lime (which raises pH) to your blueberries’ soil, it could harm those plants. Plants cannot absorb available nutrients if they are growing in a pH they don’t like.
The WV Extension Service will analyze your soil free of charge; this service was recommended over store bought soil test kits. Information regarding the testing service is available online at the WVU Extension Service. The following are a few suggestions for better soil sampling:
• Refer questions to Michael.Harmon@mail.wvu.edu or 304-728-7413 ext 2.
• Download the WVU Soil Test Form.
• Providing your email address ensures the most rapid return of your soil analysis results.
• Soil sampling MUST be done systematically, that is, gather your samples from specific portions of your garden; maybe divide your garden into quadrants or a grid and sample each quadrant, then label each sample so that you know where you took it from in your garden.
• Collect about a coffee cup size of DRY soil for each sample. The soil must be dry; you can air dry it yourself on newspaper before sending it for analysis. Do not use the oven or microwave for drying.
• Do not contaminate your own soil samples, use clean instruments not a shovel recently used on cow manure which would alter your results significantly
• List your garden “size/units” – are you gardening on feet of land or acres? Recommendations for soil amendments are provided based on your gardens units. For example, do you need to add tons per square acre or pound per square foot to your garden space? Providing correct units will make it easier to add the recommended nutrients to your garden without lengthy math calculations.
• List the plants you plan to plant, this ensures that your recommendations will be tailored to those plants feeding needs.
• The soil sample test results will provide you with information on your pH, P, K, Ca, Mg; no N (Nitrogen) results will be provided. N is a water soluble nutrient and varies with rain fall. The extension service recommends on average 2 pounds of Nitrogen per 1000 square feet of soil.
• Nutrients take time to improve the soil quality and you may not see immediate results in your plants growth after adding recommended nutrients.
A useful handout was provided, the WVU Lawn & Garden Tool Care Guide. Highlights:
• Clean dirt off of your tools between uses to avoid cross contamination of diseases between plants.
• Keep your tools sharpened and oiled to make your work easier, even hoes benefit from sharpening. Tool sharpening can be done by Boltz Hardware in Martinsburg and intermittently by vendors at the Charlestown farmers market.
• Make a sand bucket (bucket filled with sand and oil) and use it to clean, sharpen and oil/rust proof your tools. Remember motor oil can be used in your sand bucket but it is not organic, vegetable oil can be used but it will become rancid. More info is available online.
Row Covers and Tunnels
Tunnels both low and high versions are an economical way to extend your vegetable growing season both earlier in the Spring and later into Winter, to shield your crops from sunlight and to protect your vegetables from destructive insect pests like flea beetles and cabbage loppers. These tunnels are smaller/shorter and can’t be walked into but they are much less expensive than traditional greenhouses. Low tunnels extend the growing season about 2-3 weeks while high tunnels allow 6-8 weeks of additional growing time. Information will be available on the WV extension service website soon.
How to Make a Low Tunnel
• Bend 9 gauge wire into a 60–72 inch half circle about 18 inches high and push the ends about 4 inches deep into the soil along the planting row in your vegetable garden. Continue to make and place the wire frame half circles about 3–4 feet apart down the row until the entire row is trellised.
• Plant your seedlings
• Cover the tunnel with light or heavy weight row cover fabric.
• Secure the fabric to the top and bottom of the wire frame with clips, like binder clips if you think its necessary for these low tunnels, secure the bottom edge with weights, wire ground staples or bury it in the soil.
• Tie off row cover at the ends at ground level and secure
• Row cover supplies are available premade at Home Depot, Martins Produce in Shippensburg, PA, Valley Produce in Harrisonburg, PA , Southern States, Snavely’s and from online vendors such as Johnny’s Select Seeds.
How to Make a High Tunnel
• Cut a 10 foot length of half inch conduit pipe available at Home Depot
• Measure and mark at 16 inches at both ends of the pipe
• Using a pipe bender, insert the pipe into the pipe bender until the 16 inch mark lines up with the strap.
• Remember to keep the pipe flat and level as you bend it around the bender.
• Bend half of the pipe around the bender, remove the pipe from the bender
• Insert the other end of the pipe into the bender until the 16 inch mark lines up with the strap
• Bend that half of the pipe, now you should have a perfect half circle about 4 ft high and 4 ft wide.
• Pound 2 pieces of metal rebar(12-16 inches long) part way into the soil on either side of your garden row where you want to put the ends of your half circle.
• Place the half inch, conduit pipe, half circle over your rebar stakes. Continue to make and place the metal frame half circles and rebar stakes about 5 feet apart down the row until the entire row is trellised.
• You don’t have to use rebar stakes, it just makes placing the ends of the high tunnel frame easier and gives you a higher tunnel, because the rebar is already pounded deep into the soil.
• High tunnels require a top rail bracing bar between half circles to provide stability. Secure the top rail with electrical tape, or PVC couplers (available premade).
• Plant your seedlings
• Cover the tunnel with light or heavy weight row cover fabric.
• Secure the fabric to the top and bottom of the wire frame with clips, like binder clips secure the bottom edge with weights, wire pins, bury it in the soil or use another length of rail pipe attached to the edge with clips to allow raising and lowering the cover like a curtain.
• Tie off row cover at the ends at ground level and secure or make another curtain.
• Row cover supplies are available premade as listed above.
• The Gardeners Exchange Group has been given permission to use the pipe bender at the extension service free of charge and as such we are planning a High Tunnel bending party, date to be decided, BYOP, bring your own straight pipe to be bent.
A Few Notes About Row Cover Fabrics
• Row cover fabric can be used mid season to keep off pests but bear in mind that this also keeps off beneficial insects like bees and other pollinators. Some plants absolutely require pollinators to produce fruit, some plants benefit by the presence of pollinators.
• Light weight row cover fabric allows 85% light transmission and IS rain permeable.
• For winter protection from cold use 2 layers of light weight row covers or buy the 1 – 1.25 oz variety of thicker row cover fabric.
• For additional snow protection and to shed snow use a top cover layer of heavy gauge (4-6 mm) construction plastic secured over the top of the row cover/s.
• When the temperature rises above 70 degrees, you might have to consider venting the rows
Commercially produced greenhouse kits are available such as the Rimol Rolling Green House (Known as the Rolling Thunder) used at the Jefferson Extension Service location. This plastic green house is 30 X 72 feet and rolls along a metal runner placed on the ground. Mobility (theoretically) allows the greenhouse to be rolled over fixed location plants like raspberries to lengthen the berry production season. A large greenhouse like this costs about $10-15,000. Using low tunnels inside this greenhouse allows all season vegetable production. Drip irrigation and timers are used inside the greenhouse. Watering is reduced during the winter growing season. Favorite winter vegetable varieties include Bolero carrots- these were reportedly sweet delicious (use pelletized seeds for best results), spinach and kale. Inside the greenhouse once the plants bolt and produce seeds you can sell the seeds to various vegetable seed companies. Ext Service has more details.