By Janice Gestner, Master Gardener
As the weather warms, vegetable gardeners are eager to get into their gardens to plant and harvest all summer long! The enthusiasm is wonderful, but there are a few things to consider before planting begins.
First, if you have not tested the soil in the last couple of years, do so as soon as you can scoop samples from your garden. A soil test will give you information on how to have the best soil possible in your garden space. Guessing does not give you good answers! Check this site at the University of Minnesota for instructions about how to take and submit soil samples for testing. University of Minnesota Soil Testing Laboratory. For $17.00, they will return information to you on the health of your garden soil including its pH, soil texture, organic matter and suggested amendments. When you do prepare your garden soil for planting, be sure that the soil is not too wet or too dry. If a small ball of soil crumbles in your hand when pressed, it is probably just right.
Clean Your Tools
While you are waiting for your soil test results, you will have time to get your gardening tools and containers ready. Disinfect them, if you did not do it in the fall, to rid equipment of leftover bacteria, viruses and fungi. Healthy soil and clean tools will help you avoid disease on the plants later in the season. University of Minnesota Extension recommendations for best disinfectants can be found here.
Create a Garden Plan
Creating a plan for vegetable arrangements before you start planting will help you determine priorities and proper spacing for every plant. You will have to take into consideration the amount of sun you have, spacing requirements for each plant along with the size of your garden, and quantity you want for each variety. Measure your garden area and then consider the space requirements for each of the plants you have chosen. For example, most tomatoes need to be spaced two to three feet apart. Pepper plants need to be spaced eighteen to twenty-four inches apart. Each plant has its specific needs. Gardeners can either work on graph paper to figure out space requirements or use an online garden layout planner. Some are free and others are inexpensive, such as “Grow Veg”. These online programs will allow you to work with your plan, revise it as often as needed, and give you advice on spacing and requirements. You may want to plant all your early maturing plants like lettuce and spinach together so you can use the space for a later crop after harvesting them.
Plant Vegetables at the Appropriate Time
Next, garden vegetables each have their individual soil and air temperature needs. Some grow best in cooler weather while other vegetables like tomatoes, peppers, and melons require warm weather and soil. If you have the time, space, and correct lighting, you can start many plants indoors such as tomatoes, eggplants, melons, peppers, etc., and then transfer them to the garden after hardening them off for at least a week. Also, remember that the weather in Minnesota can be very changeable. A week of warm weather can be followed by frost. Better to be safe with the warm weather plants and plant them the last week of May or first week of June. Early season crops include lettuce, kale, carrots, broccoli, and more. Warm season crops include beans, melons, squash, tomatoes, corn and more. For a more complete chart of when to plant vegetables go to “Planting the Vegetable Garden” at the University of Minnesota Extension. Plants and seeds should be watered initially and kept consistently watered throughout the season.
Benefits of Mulching
There are many benefits to adding either an organic mulch or inorganic plastic film mulch to cover the ground around plants in a vegetable garden. Mulches help to eliminate weed germination, keep soil temperatures moderate so there is less stress on the plants, and improve soil moisture retention by eliminating evaporation from the soil. A huge benefit of mulch is that it can reduce disease by keeping soil from splashing up onto a plant’s foliage during rain or watering. Last, there is less soil compaction with the protection of a layer of mulch.
Apply organic mulch after plants are up and established. Keep the mulch two to three inches away from the stems of your vegetables. The depth can vary, but is usually two to three inches. Common organic mulches include shredded dry leaves, dry, chemical-free grass clippings, straw, cocoa bean hulls, and compost. Adding newspaper under these mulches also helps to keep weed seeds from germinating. Finally, organic mulches can break down over the season and become soil amendments.
Inorganic mulches, like black, red, and silver plastic film, can also benefit your garden. It should be laid down immediately after transplanting plants such as tomatoes, peppers, eggplants or other vegetables you have started indoors. Or, it can be applied after directly seeded vegetables are up and established. Make sure to create holes three inches in diameter for your vegetable plant stems. According to Clemson University, after testing tomatoes grown with red plastic film mulch, tomato yields were boosted by 20%. Silver plastic film mulches have been found to help reduce insect pest issues for cucumbers and squash. Master Gardeners in Dakota County are using the silver plastic film mulch on our South St. Paul Seed Trial Garden this summer to evaluate pest control. Inorganic mulches tend to be more expensive than inorganic mulches.
May is an exciting time in the vegetable garden. But taking the proper steps to prepare, plan and plant will yield an exciting harvest as well. Happy planting!