Fresh herbs are always welcome ingredients in home cooking and ones which home cooks can't seem to get enough of. They are also great for bringing indoors and adding freshness to the home with their fragrance. An herb garden is easy to start and even easier to maintain. Minnesota summers are great for growing herbs. Because Minnesota is in USDA zones 3 and 4, cold country for sure, you will need to plant your herbs in late spring after all danger of frost has passed. That's about the last week of May in the south and the first week of June in the far north.
Choose a sunny and well-drained site for your new herb garden. A place easily accessible to the kitchen is ideal.
Prepare the soil by mixing in 1/3 to 1/2 compost about 12 inches deep. Most Minnesota soils are well-suited for growing herbs when amended in this way. Heavy clay soils will have to be amended with more material; 1/2 to 2/3 added conditioning with compost, sand, gravel or finely shredded bark would not be too much.
Dig a hole for each plant and tuck the plant into the hole, tamping lightly to eliminate air pockets. Give each herb the space suggested on the label. Herbs have tender leaves and will mildew if they grow too closely together.
Water each plant as it goes in the ground so it is moist but not waterlogged.
Mulch the area with 1 inch of shredded bark or 1/2 inch of pea gravel. Heavier mulches, like pea gravel, help keep soil from splashing onto your herbs during rain showers.
Water the soil under the herbs sparingly as it becomes dry. Overhead watering encourages mildew in humid Minnesota summers.
Maintain the size and shape of your herbs by snipping them often for use in the kitchen.
Mulch woody herbs like lavender and hardy rosemary in mid-September to protect their roots from winter cold. Apply about 2 inches of mulch.