Dear Master Gardener: Every year at this time I say "This year I'm going to really 'do' my lawn right." It never happens. But this year I really mean it. What should I do to get off to a good start on a good lawn?
Answer: Grass needs water, oxygen (air), nutrients (most especially nitrogen) and sunlight in order to thrive. Your goal should be to provide those basics. Start by staying off the grass until the lawn is snow-free and dry. Walking on a wet, spongy surface compacts the soil and damages tender, young grass. While you are waiting, get your lawn soil tested and buy fertilizer that contains what the test shows that your lawn needs. Next pick up winter debris-twigs, cones, paper, etc., and do a thorough but gentle raking with a leaf rake, not a rigid-metal one. Then apply your spring fertilizer and water it in well. Follow the spreading instructions printed on the bag, being especially careful to follow the calibration to avoid fertilizer burn. Many people spread at half strength in paths perpendicular to one another to avoid burning. If you had crabgrass problems last year, spread crabgrass preventer around Memorial Day. Spread too early, it will leach away before the crabgrass germinates. Mow regularly to a height of 3-3 1/2 inches, leaving the clippings on the lawn to add nitrogen to the soil as they decompose. For the rest of the summer, try to make sure that the lawn receives an inch of water a week by rain or sprinkler. A small container placed within the perimeter of the sprinkler path can be your measure. Early morning watering is the most efficient because cooler temperatures and sun angles minimize evaporation. If you have pets whose urine has burned spots in the grass, flush those areas well with a hose. If that doesn't help, you will need to dig up the dead grass and reseed. If your lawn is heavily used (playing children, heavy equipment travel, etc.), the soil may be compacted to the point where grass roots struggle to penetrate. In that case, rent a heavy-duty aerator, which will throw up 2-3 inch plugs of soil, allowing air and water to enter. Leave the plugs on the lawn surface where they will disintegrate. In September apply a second (and final) fertilization, encouraging a strong, healthy lawn, ready for spring.
Dear Master Gardener: There are very bright, colorful flowers in small pots for sale in some stores. What are they and are they indoor or outdoor plants?
Answer: You are most likely referring to Primula, or primrose. They are a delightful indoor plant bringing a cheery blast of spring color to the indoors; as well as a perennial garden plant. Primula come in a variety of colors and sizes, but all grow a rosette of green, oval-shaped leaves with the flowers standing above the foliage. To get the most from an indoor primrose plant, keep it in a place that gets bright light, but not direct sunlight, and keep it evenly moist and cool. If you have purchased the primrose at a store and would like to try to keep it after it is done blooming, you can cut out the old flower stems, plant it in your garden and see if you happen to have the perennial variety. There are cold hardy, perennial primulas that make great additions to the early spring garden and do well in our area. There are different species that come in a variety of sizes and colors. Auricula primrose is a low-growing species that is hardy to Zone 3 and has fragrant, bright yellow flowers. Primula denticulata, also known as drumstick primrose, reach 8-12 inches and have a globular flower form. Primula polyantha reach 6-12 inches and make a nice addition to an outdoor miniature garden. Plant Primulas with lots of organic matter in a cool, partly shaded location.
Dear Master Gardener: Do forsythia grow well in this area?
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Answer: Forsythia are non-native shrubs that are some of the earliest to bloom. Flower bud hardiness can be a limiting factor to growing forsythia in Minnesota. Cultivars that are flower bud hardy and provide reliable bloom in hardiness zones 3b-5 include Meadowlark, New Hampshire Gold, Northern Gold, and Northern Sun. University of Minnesota cold hardiness testing showed these cultivars to be flower bud hardy to 33 degrees below zero, although they may still suffer occasional flower bud mortality during mid or late winter thaws. Forsythia 'Meadowlark' is one of the hardiest varieties, with prolific yellow flowers and a more controlled habit than the species. At maturity it will reach about nine feet tall with a spread of seven feet. Forsythia bloom best in full sun, but will tolerate partial shade. It is relatively low maintenance, adaptable to dry and moist locations and should do fine under average home landscape conditions. Only prune forsythia after flowering. This is a plant that deer typically leave alone!
Dear Master Gardener: I've always been intrigued by Jack-in-the-Pulpit and was wondering if I could add it to my woodland garden.
Answer: Jack-in-the-Pulpit (Arisaema triphyllum) can be an interesting addition to shade and woodland gardens. It is a native of moist eastern woods as far west as Minnesota and is hardy into Zone 3. The "pulpit" is a spathe that is light green to purplish green, often with purple and green stripes. The "Jack" is a flower bearing spadix with either male or female flowers or some of each. Female flowers produce the bright red berries you see when the spathe dies and falls away. The red berries, as well as all other parts of the plant, contain needle-like crystals of calcium oxalate that can cause irritation to sensitive skin when touched and swelling and burning of the lips and tongue if eaten. If plant parts are swallowed, which is unlikely due to the immediate, intense burning sensation, it would require medical attention. Jack-in-the-Pulpit is tolerant of a wide range of soil pH, but grows best in moist, well-drained soil, high in organic matter. It thrives in dappled to deep shade. Do not collect Jack-in-the-Pulpit plants from the wild. It is illegal to dig up any plant on public lands without a permit. Jack-in-the-Pulpit is not an endangered species. They can be purchased from nurseries specializing in native plants and wildflowers. Some garden centers may also carry them in the spring. You may be able to buy seeds by mail order or get seeds in early fall from a friend's plant. If so, don't let the seeds dry out and sow them where you want them to come up the next spring, by covering the seeds with 1/4 to 1/2 inches of soil.
APRIL GARDEN TIPS
• Remove tree wraps and rose cones.
• Make sure your watering system is in order.
• Plant cold-hardy vegetables, such as beets, chard, kale, onions, peas and spinach.
• Flowers that may be planted now are pansies, violas, Johnny-jump-ups, and snapdragons.
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• Gently and gradually pull back mulch on roses, perennials and bulbs. Recover them if evening temperatures are predicted to be below freezing.
• Test your soil to see which nutrients need to be added.
• Resist the temptation to rake your lawn until it has dried a bit.
• Prepare your lawn mower for the season by changing the oil, replacing the spark plugs and sharpening the blade.
• Trim perennials, cutting off dead leaves and stalks but being careful not to harm new growth that may be hidden in winter debris.
• Divide summer and fall-blooming perennials when they are 3-4 inches tall. Wait until fall August or September to divide spring-blooming perennials.
University of Minnesota Extension Master Gardeners are trained and certified volunteers for the University of Minnesota Extension Service. All information given in this column is based on university research. To ask a question, call the Master Gardener Help Line at 218-454-GROW (4769) and leave a recorded message. A Master Gardener will return your call.
