Chicago Botanic Garden Spring 2020

26 chicagobotanic.org Q. I have many plants that bloom in the spring and summer. What perennials can I plant now that provide that same burst of color late in the growing season and have good fall color? A. It is true that many garden centers pro- mote early-blooming plants, but there are also many fall-blooming perennials avail- able at this time of year. Some of the most popular fall-blooming plants are ornamen- tal grasses. Some perennial grasses re- quire a longer period of warm weather and may not bloom in years when the growing season is shortened by early cold tempera- tures. Some ornamental grasses that will bloom in shorter growing seasons are feather reed grass (Calamagrostis × acuti- flora ‘Karl Foerster’), fall-blooming moor grass (Molinia caerulea) selections, and red switch grass (Panicum virgatum ‘Haense Herms’ or ‘Rotstrahlbusch’). Noth- ing says fall better than mums (Chrysan- themum). Some growers force mums to bloom in the spring so customers can ob- serve their brilliant colors of white, yellow, gold, pink, red, orange, bronze, maroon, Gardening Ask the Experts rust, and purple. The chance of mums re- turning year after year is greater if they are planted in the spring. Asters are also a common fall-blooming plant but can be more difficult to find at garden centers in the spring. Japanese and hybrid anemones (Anemone hupehensis var. japonica ‘Pami- na’, A. ‘Honorine Jobert’, and A. ‘Max Vo- gel’) are top performers and provide color late in the season. And, of course, no fall garden is complete without beds of bright, yellow goldenrod (Solidago) and coneflow- er (Rudbeckia). Last, but not least, for a beautiful drift of fall foliage color, try Arkan- sas amsonia (Amsonia hubrichtii) . The real merit of this plant is not the blue flowers in the spring, but rather the golden shade of its foliage in the fall. When planning your garden this spring, don’t forget to think about fall. Plant Information Service is sponsored by Q. I use many green onions in my cooking. Can I grow them in my home vegetable garden? A. Green onions (scallions) are readily grown in home gardens. Using onion sets (available in early spring from some garden centers or catalogs) is the simplest method for home gardeners. White onion sets are usually preferred; red or yellow sets can also be used. Sets having a diameter larger than a dime are better for green onions. Plant the sets in the early spring, as soon as the soil can be worked, at a depth of 1½ inches and close enough to touch one an- other. Control weeds with shallow cultiva- tion and hilling. For longer white stems, pull loose soil toward the onions with a hoe when the tops are 4 inches tall. Pull green onions at any time after the tops are 6 inches tall. Green onions become stronger in flavor with age and increasing size. Learn more Send your plant questions to plantinfo@ chicagobotanic.org or call (847) 835-0972. You may also bring plant samples to the certified University of Illinois Extension Master Gardeners at the Plant Information Desk in the Regenstein Center. Anemone hupehensis var. japonica ‘Pamina’ Plant ornamental grasses now for fall garden interest.