Dear Master Gardener: I would like to harvest lotus seed pods for flower arrangements. I’ve heard it’s a good time to walk along the shores of lakes and find those that have washed up on the shore. Where can I find them?
To respond: The lotus is Minnesota’s largest native wildflower, with stunning pale yellow blooms 6 to 10 inches across. The fragrant flowers close at night and last only two days. Lotus plants are typically found in the still waters of the Mississippi and Minnesota rivers, and some lakes in the Twin Cities area. According to Friends of the Mississippi River, the lotus was an important food source for Native Americans because almost the entire plant is edible. The unusual seed pods are often used in flower arrangements and can be found in some craft stores, although it is not certain if these are native lotuses. In Minnesota, the American lotus is a protected wildflower – no harvesting of the plant is permitted. You’re probably safe picking up seed pods that aren’t attached to the plant and have washed up on the shore (unless it’s private property without permission).
Dear Master Gardener: I would like to add some color to my landscape with shrubs. Is potentilla a good shrub to plant in a sunny location?
To respond: Yes it is! Although some people turn their noses up at them because they’re used so much in commercial landscaping, there are plenty of good reasons why they’re in commercial landscapes. Many varieties are extremely hardy, have a very long flowering time, are relatively disease and insect free, resistant to rabbits and deer, can withstand drought, and thrive in warm, open sites with full sun. Most are hardy to 50 degrees below zero. They can be used as an informal hedge or in rock gardens or as foundation plantings or in mass plantings. They need to be pruned regularly to look their best. As the stems age they produce fewer flowers, so a third of the oldest stems can be cut back each year to reinvigorate the plant or all the stems can be cut back to the ground every three years. Golden, white and yellow varieties retain good color in the summer heat, while orange, pink and red flowers fade poorly. Pink Beauty is a pink variety that retains its color the best. Keep the soil evenly moist, especially the first three years as they become established. Fertilize them each spring with a 10-10-10 fertilizer.
Dear Master Gardener: I would like to put in a herb garden. What herbs are typically planted in an herb garden?
To respond: According to the Colorado State University Extension, a basic culinary garden contains garlic, chives, basil, oregano, parsley, sage, rosemary, and thyme. A tea garden may have spearmint, peppermint, lemon balm, lemon verbena, chamomile, and catnip. A potpourri garden can have lavender, scented geranium, santolina, and rosemary. Once established, most herbs require little water, but annual herbs and mints require slightly more water than perennial herbs.
Dear Master Gardener: I am interested in growing hops this year. What varieties do you recommend and when should they be planted?
To respond: With the popularity of beer brewing, hop cultivation has become very popular. The University of Minnesota Hops Research Program has more than 16 varieties tested at research sites in Waseca, Rosemount and Grand Rapids. Cultivars to look for that are disease resistant and cold hardy are: Centennial, Nugget, Sterling, and Cascade. Aurea is a fast growing, very cold hardy golden leaf cultivar. The most common and economical way to get hop plants is to buy rhizomes (underground stems), but you can also buy them as potted plants. The rhizomes should be planted with the buds upwards, in early spring as soon as the ground is passable. Potted plants can be planted at any time during the growing season. Plant in full sun in well-drained soil rich in organic matter.
Dear Master Gardener: Are the leaves of the horseradish plant edible or poisonous?
To respond: There are recipes for preparing horseradish leaves, but so are warnings about their toxicity. According to Susan Mahr of the University of Wisconsin Extension, “the leaves are edible raw or cooked, but rarely eaten”. The Montana State University Extension and the Oregon State University Extension list the leaves of the horseradish plant as poisonous. According to North Carolina State University Extension, the edible parts are the roots, which are used as a condiment, but only in small amounts. Additionally, the leaves, as they develop in the spring, can be boiled in salted water until tender, then eaten with butter or margarine. They also note that “horseradish is not poisonous unless large amounts are consumed.”
Horseradish plants belong to the Brassica family, so their leaves, as well as the roots, produce glucosinolates, which are the enzymes that give the roots their spicy flavor. In large amounts, these enzymes can be toxic, but in most cases eating horseradish is safe.
You can get your garden questions answered by calling the new Master Gardener Helpline at 218-824-1068 and leaving a message. A master gardener will call you back. Or, email me at [email protected] and I’ll reply in the column if space permits.
The University of Minnesota Extension Master Gardeners are trained and certified volunteers for the University of Minnesota Extension. The information provided in this column is based on academic research.