As fall approaches, many perennial plants are ready to go dormant for the winter. Now is the time to start thinking about next spring’s floral display and planting spring-flowering bulbs.
Since spring bulbs need a cold period during the winter in order to bloom, the best time to plant is late September through October to allow sufficient time for a good root system to develop.
Investing a little time and money in the fall will pay off greatly next spring when you start seeing pops of color blanketing your garden, Depending on the location, spring bulbs, such as snowdrops, begin blooming in late February and continue until late June with alliums.
Bulbs should be firm and free of rotting spots or signs of disease. When buying bulbs, keep in mind that larger bulbs will produce larger blooms,
If the bulbs cannot be planted immediately after purchasing, store them in a cool, dry place away from ethylene-producing fruits, such as apples, bananas, melons, pears, and peaches to prevent flowering disorders.
For the greatest visual impact, plant bulbs in groupings and large drifts or waves of color. Mix them in with other perennials and shrubs to screen the foliage after blooms fade. To produce maximum blooms, most bulbs will need at least eight hours of sunlight daily.
Most bulbs require fertile, well-drained soil to prevent the bulb from rotting. Poorly drained soil can be improved by adding organic matter such as compost or peat moss. The material should be incorporated into the soil before planting at a rate of four-parts soil, one-part organic matter. A balanced fertilizer, 20-20-20, can also be incorporated into the soil at this time.
The general rule of thumb when planting bulbs is to plant them two to three times the length of the bulb, measured from the bottom of the bulb,
Large bulbs, such as daffodils or tulips, should be planted 6 to 8- inches deep. Small bulbs, such as snowdrops and crocus, should be planted 3 to 4 inches deep. Bulbs should be spaced 6 to 12 inches apart to allow for the spread and future divisions. Plant bulbs with the nose of the bulb facing upward and the root plate facing down.
After covering the planted bulbs with soil, water the area well to settle the bulbs into the soil and initiate root development. If there is little rain in the fall, continue to water weekly until the ground freezes. A light, 2-inch layer of mulch can be added after planting to minimize effects of winter temperature fluctuations and to help converse soil moisture.
“Spring bulbs can vary in flower color, timing, height, and shape depending on the species and variety, Add a new type of bulb each fall to have a beautiful mix of spring bloomers in your garden.”
SOURCE: Brittnay Haag, Horticulture Educator, Illinois Extension
Asters are daisy-like perennials with starry-shaped flower heads that range in color from white to blue to purple. They bring delightful beauty to the garden in late summer and autumn, when many of our summer blooms may be fading. Here’s how to grow asters in your garden!
There are quite a few species and varieties of asters out there! The two most commonly encountered asters in the home gardening world are the New England aster (Symphyotrichum novae-angliae) and the New York aster (S. novi-belgii), but you will see a range of hybrid varieties available in showy pinks, blues, and purples at garden centers. “Wild type” species native to your region may also be available and are generally a wise choice ecologically speaking, despite not being as flashy as the cultivated varieties. Learn more about recommended varieties further down this page.
Asters also attract bees and butterflies, providing the pollinators with an important late-season supply of nectar. Thanks to the aster’s late bloom time, they are sometimes called “Michaelmas daisies,” which refers to the holiday of the same name that occurs annually on September 29.
The plant is versatile and can be used in many places—borders, rock gardens, or wildflower gardens, to name a few. Depending on the variety, the plant’s height can range from 8 inches to 8 feet, so you should be able to find one suitable for your garden.
Add a thin layer of compost (or a portion of balanced fertilizer) with a 2–inch layer of mulch around the plants every spring to encourage vigorous growth.
If you receive less than 1 inch of rain a week, remember to water your plants regularly during the summer. However, many asters are moisture-sensitive; if your plants have too much moisture or too little moisture, they will often lose their lower foliage or not flower well. Keep an eye out for any stressed plants and try a different watering method if your plants are losing flowers.
Stake the tall varieties in order to keep them from falling over.
Pinch back asters once or twice in the early summer to promote bushier growth and more blooms. Don’t worry, they can take it!
Cut asters back in winter after the foliage has died, or leave them through the winter to add some off-season interest to your garden.
Note: Aster flowers that are allowed to mature fully may reseed themselves, but resulting asters may not bloom true. (In other words, you may not get the same color flowers that you originally planted!)
Divide every 2 to 3 years in the spring to maintain your plant’s vigor and flower quality.
Susceptible to:
Powdery mildew
Rusts
White smut
Leaf spots
Stem cankers
Aphids
Tarsonemid mites
Slugs and snails
Nematodes
Asters work well as cut flowers! Here’s how to cut and keep flowers fresh.
The most common asters available in North America are the New England aster (Symphyotrichum novae-angliae) and the New York aster (Symphyotrichum novi-belgii). Both of these plants are native to North America and are great flowers for pollinators. We recommend planting a native species of aster over a non-native species when possible, so talk with your local Cooperative Extension or garden center about which species are best suited to your area.
New England asters (S. novae-angliae): Varieties have a range of flower colors, from magenta to deep purple. They typically grow larger than New York asters, though some varieties are on the smaller side.
New York asters (S. novi-belgii): There are many, many varieties of New York asters available. Their flowers range from bright pink to bluish-purple and may be double, semi-double, or single.
Blue wood aster (S. cordifolium): Bushy with small, blue-to-white flowers.
Heath aster (S. ericoides): A low-growing ground cover (similar to creeping phlox) with small, white flowers.
Smooth aster (S. laeve): A tall, upright aster with small, lavender flowers.
Frikart’s aster (Aster x frikartii) ‘Mönch’: Hailing from Switzerland, this mid-sized aster has large, lilac-blue flowers.
Rhone aster (A. sedifolius) ‘Nanus’: This aster is known for its small, star-shaped, lilac-blue flowers and compact growth.
One of the reasons daylilies are so popular is because they are some of the easiest perennials to grow and can survive much neglect, drought, and other adverse conditions. However, if you want your daylilies to look their best, they will benefit from the periodic care described below.
Water is the most essential factor in growing healthy, beautiful daylilies. Daylilies love water during the growing season and prefer about an inch of water per week. In many areas, regular rainfall will supply much of that amount. In areas where rainfall is less consistent, supplemental watering will benefit your daylilies enormously. Supplemental water can be applied overhead through sprinklers or by hand or through drip irrigation systems.
Daylilies grow well in any reasonably fertile garden soil. However, a little extra fertilizer can work wonders. If you fertilize only once a year, do so in early spring as new daylily top growth emerges. Spread a handful of any general purpose fertilizer such as 5-10-10 or 10-10-10 around the base of each daylily clump. In areas that receive regular rainfall, the fertilizer does not have to be watered in. In other areas, watering the fertilizer in is beneficial.
If you are able, it is a good idea to fertilize your daylilies a second time during the year, a few weeks after they are finished blooming. This will help your plants multiply faster and deliver a stronger bloom performance the following year.
Deadheading daylilies is really a matter of personal preference and is not essential to growing healthy plants. Most public gardens, major landscape plantings, and highway roadside plantings of daylilies are never deadheaded. However, daylilies look their best when spent blossoms are removed. The removal of wilted blossoms also inhibits seed set. If maintaining a neat garden is not a priority for you, the spent blossoms will usually fall from the scape in a few days. Leaving lots of spent blossoms on large-flowered daylily plants may leave them looking a bit untidy, so many gardeners simply snap off the spent blossoms as they stroll through the garden admiring their plants. Once all of the flowers have blossomed on a scape, you can cut the entire scape back to the ground. If you do not cut it back, it will simply turn brown and remain standing until you cut the entire plant back in the fall.
Some daylily cultivars, especially older types, are extremely fertile and set seed pods readily as the natural result of wind or insect pollination. If these seed pods are allowed to mature and spill their seed in and around the clump, some “volunteer” seedlings may grow up around the original plant. If you allow these seedlings to grow and bloom, you will notice that their flowers do not look like the original parent plant. If you hadn’t realized that these plants were seedlings of your original plant, you may wonder if your daylily is changing its characteristics. It is not. Daylilies are genetically stable and are not prone to sporting like some other perennials are. If you do not want to keep these volunteer seedlings, simply dig them out and discard them. If you do not want to deal with volunteer seedlings again, be sure to remove the seed pods before they drop their seeds next time.
Once you have had several hard frosts in your area, the foliage of your daylilies will turn brown and dry up. Some gardeners choose to remove this dead foliage in the fall while other gardeners prefer to leave it in place as a form of winter mulch and then remove it in the spring. Years of observation by experienced daylily growers have revealed no difference in plant performance the following year regardless of when the dead foliage is removed. Whatever works best for you is just fine. Just be sure that all the dead foliage is gone by the time the new growth resumes in the spring.
After remaining in place undivided for four years or more, most modern daylily cultivars will show some gradual decline in bloom quantity and quality. This is their way of telling you that they are ready to be divided. When daylily performance begins to go downhill, it is time to dig and divide the overgrown clump. Daylily division is a relatively simple task but requires a bit of muscle if the clumps are large. Though it can be done any time the soil is workable, it is best done right after the daylily has finished blooming.
Daylily division can be done a number of ways. If the clump is not too large, you could simply cut the clump right down the middle with a shovel and dig out one of the halves, leaving the other half in place. If the clump is fairly large, it would be better to dig out the entire thing and divide it down from there.
If you choose to dig out the entire clump, grab a shovel or gardening fork and a tarp. Lift the entire clump from the ground and shake off as much soil from the clump as possible (this is much easier to do if the soil is dry at the time). If you are planning to divide the clump way down into single fans, you may want to wash all the soil from the roots using a garden hose with a sharp stream nozzle to make the job easier. If you are just going to separate the clump into a few pieces, washing the soil off is not necessary or recommended.
With the clump sitting on your tarp, use your shovel or a sharp knife to divide the clump down into smaller pieces. Don’t worry about slicing through the crown. Daylilies have enormous regenerative and recuperative capabilities, and healthy new plants will develop even from damaged crowns. It is best to leave three or four fans in each division so that your new plants will still be showy bloomers the following year. If you need a lot of divisions to fill a large area, it will not hurt the plant to divide it down into one fan divisions. However, these small divisions will require a bit longer growing time to redevelop into showy clumps. Discard the old, woody center of the daylily clump; it is no longer productive and you have plenty of healthy new divisions to work with now. If you have extra plants, offer them to friends.
It is best to plant your new daylily divisions as soon as possible after they have been made. You will likely have many more than can fit in the original location. Hopefully you planned ahead and have thought about where you are going to plant them! Plant them at the same level they were growing at originally, with the crown approximately one inch below the soil line.
Turn your patio or balcony into an exotic tropical getaway with the help of bold, beautiful tropical plants. Used as dramatic summer annuals in trendy decorative containers, tropical plants with rich foliage or sizzling-hot blooms turn outdoor spaces into hot spots for relaxation and entertaining.
From birds of paradise and flowering gingers with striking, vibrant blooms to elegant tropical hibiscus and rich, green palms, tropical plants have different needs than plants from more mundane locales — especially when it comes to nutrition. Keeping tropical plants at their peaks of beauty and performance means meeting the following specialized, yet simple, needs:
When you think of tropical climates, your first thoughts might be of hot, sun-drenched shores. However, many popular tropical plants are “understory” plants that live beneath taller plants in tropical jungles. Tender tropical foliage can sunburn, just like human skin, when moved quickly into hot, direct sun. When plants are used to indoor living, in homes or stores, the results can be unappealing.
Allow tropical plants to acclimate gradually to new light levels whenever you move them, whether the change is from low to bright or vice versa. For most tropical plants, bright, indirect light and protection from the sun’s most intense, midday rays is best.
Good drainage is essential for tropical plants, especially when they’re placed in containers where water can’t move as freely as it does in loose, rich, jungle soils. Tropicals don’t do well when their roots stay wet, and soggy, poor-draining soil saps their health and beauty quickly.
Always choose planting containers with good drainage holes, so excess water can run through. If you use decorative containers as cache pots, with your planting pot tucked inside, keep them free from standing water. For container planting, look for a lightweight, commercial potting mix labeled for containers. Add in earthworm castings for extra organic matter, and you’ll have a mix ideal for tropical plants.
To stay healthy and lush, tropical plants need less phosphorus relative to other primary nutrients. On a fertilizer label, this means the middle number of the “NPK” trio — nitrogen (N), phosphorus (P) and potassium (K) — is lower than the other two. To keep their rich colors intact, tropicals also need more iron and magnesium than most common plants.
Many gardeners have learned to give blooming plants more phosphorus to promote flowers, but tropical bloomers need just the opposite. Use a fertilizer formulated especially for tropical plants, contains lower phosphorous relative to other nutrients, along with added iron and magnesium to support beautiful foliage and bold, tropical blooms.
Soil in containers is more exposed to heat and drying winds than soil that’s protected under the surface of a garden. As a result, soil in outdoor containers dries out much faster than garden soil underground, especially under hot summer sun. Outdoor containers need regular monitoring and frequent, thorough watering to prevent tropical meltdowns.
Water your outdoor tropicals so that soil stays moist, but not soggy. Never let them completely dry out. If drying soil pulls away from the sides of your pot, press it gently back into place. Otherwise, water will run down the sides without ever reaching roots. Mulching your container soil with a decorative mulch, such as orchid bark or light-colored pebbles, helps soil retain moisture and avoid overheating. It also gives planters a crisp, finished look.
Outdoor tropicals are prone to insects and disease, such as whiteflies, aphids, and spider mites. Visible signs of damage can be yellow spots or webs on leaves. Sevin Sulfur Dust starts killing immediately upon contact, and will not harm the plant. People and pets may enter the area once dust has settled. Apply a light dusting frequently to keep your tropicals healthy and free from insect and disease damage.
If you want to keep your patio tropicals from year to year, move them indoors when nighttime fall temperatures start dropping below 55 degrees Fahrenheit. While those temperatures won’t kill most tropical plants, they can damage the foliage and send tropical plants into tailspins of stress. In addition, fall frosts can come without warning.
Make the move indoors gradually, and give your plants as much natural light as your home allows. Place them away from heating vents, and monitor their changing needs. Once indoors, tropicals require less frequent watering and less fertilizer than they needed outside.
Calamint, Lesser Calamint
Photo credit: Stonehouse Nursery
Like a cloud of confetti, tiny white flowers (sometimes touched with pale blue) appear from early summer to fall. Undemanding and dependable, calamint provides the perfect foil for other summer bloomers and foliage. This full-sun perennial has a low mounding or bushy habit, ideal for the front of the border, rock gardens, and more.
While durable and pest-free, calamint also checks two important boxes for gardeners: bees and other pollinators work the flowers throughout the summer and the aromatic foliage is deer-resistant.
Calamintha nepeta subsp. nepeta is a favorite low-growing component in stylized meadows, matrix plantings, and other modern perennial designs. Gardeners can also create a lovely monochromatic garden with more sure-thing perennials including past PPOYs such as Anemone xhybrida ‘Honorine Jobert’ and Phlox paniculata ‘David’, or complemented with ornamental grasses such as Panicum virgatum ‘Northwind’ (switchgrass) or Schyzacharium scoparium (little bluestem).
Photo credit: Midwest Groundcovers
Hardiness: USDA Zones 5 to 7
Light: Full sun
Size: Up to 18 inches tall and wide
Native Range: Great Britain to Southern Europe (Griffiths, M. 1994. Index of Garden Plants, Timber Press: Portland, OR)
Soil: Best with good drainage – tolerates some drought once established.
Maintenance: Low-maintenance deciduous perennial. Can shear back lightly if desired to create neater habit or refresh spent blooming stems. Tolerates drought once established.
Nomenclature: What’s with the “subspecies”? Abbreviated subsp. or spp., this is a naturally-occuring, phenotypic variation to a species that is usually related to a geographic situation. This subspecies was selected for size and vigor. May also be found under the following synonyms: Calamintha nepatoides and Clinopodium nepeta.
Grower Notes: Calamintha nepeta subps. nepeta has no patents or other restrictions. Propagate by vegetative cuttings (stem or root). Vernalization not required. Spring planting yields a one-gallon in 8-10 weeks. Grow on the dry side. Smaller pot sizes not recommended. Pinch or shear if needed to shape; responds to plant growth regulators.
Because of the abundance of perennials that bloom this month, June has been designated as Perennial Gardening Month by the Perennial Plant Association.
Perennial gardens often bring to mind the classic cottage garden or vibrant perennial border, and rightfully so. Cottage gardens and perennial borders burst with a variety of colors, heights, and textures. Beautiful and evolving throughout the entire growing season, even in the depths of winter, perennial gardens are visually captivating and provide wildlife habitat.
Simply defined, the paradox of choice is being overwhelmed by too many choices. Have you experienced the paradox of choice when trying to decide which perennials to add to your garden?
With virtually endless options of perennials available, creating an entirely new perennial garden or even just adding a few perennials to your garden can be daunting. However, applying these three simple decision-making strategies will help simplify the process and should help make your best options obvious:
Where, What and How?
Is the garden located in full sun or partial sun?
If it is in partial sun; is it morning sun or afternoon sun?
Yes, it does matter. Temperatures of morning sun tends to be cooler than afternoon sun and different plants have difference heat tolerances.
Perhaps the garden is in a shady area. If so, is it in full shade, mostly shade or part shade?
Container garden or in-ground garden
A growing gardening trend (pun intended), is to create perennial container gardens and then transplant the perennials to an in-ground garden bed towards the end of the growing season. Some perennials adapt to transplanting better than others and it is important to know what time of year is best for the plant re-location project.
In general, established perennials will overwinter better when planted in the ground than in a container. However, when overwintering perennials in a container, a general rule of (green) thumb is to subtract at least one hardiness zones. For example, if you live in Zone 5, the perennials should be Zone 4 or lower. To verify the Hardiness Zone where you live check out the USDA Plant Hardiness Zone Map.
Below are a few additional tips to overwintering perennials in a container:
A large container has more mass and holds more soil. This mass provides insulation that helps moderate the soil temperature, protecting the plant’s roots from temperature extremes. The additional soil also helps retain soil moisture.
Cover the soil with organic mulch: bark mulch or leaves, or even a few layers of newspaper. In addition to moderating soil temperature fluctuations and retaining moisture, the cover helps prevent weed seeds from taking up residence in your perennial container garden.
Further protect your perennial container garden by moving it to a more protected area. Even a non-heated garage will help protect it from severe temperature extremes. Since the plants are dormant, light isn’t required, but check the container every few weeks to make sure the soil is still moist. However, be careful not to over-water as this could cause the plant to come out of dormancy prematurely.
Usually perennials are celebrated for their flowers and long blooming period, yet some are infamous for their foliage; think of Hosta, succulents, and ornamental grasses. An ever-growing (another pun?) category of perennials are those with unique foliage such as Heuchera or Ligularia, that also have notable flowers.
Consider the placement in the garden, whether it be a perennial border or container garden.
o Traditional perennial borders are essentially designed in three distinct sections: the tallest plants are placed towards the back then the mid-height plants and lastly, at the front of the border is most often a low growing flowering perennial or ground-cover.
o A perennial container garden that will be viewed from all angles, or nearly all angles, should have the tallest plant in the center, with mid-height plants surrounding the tallest plant and ultimately the shortest plants around the edge of the container. Just remember the standard container gardening design tenet Thriller, Fillers and Spillers applies in a perennial container garden just as it does for an annual container garden.
For more design ideas and garden maintenance tips read The Blogpost Pile: Coloring Your Garden with Annuals, as the ideas and tips shared in this article apply to perennials as well as annuals.
How much maintenance?
Some perennials require more maintenance to keep them blooming and healthy than others do. Understanding how much time you want to enjoy in the garden tending to your flowers, will help ensure your perennial garden thrives for years to come.
How much moisture?
Determining how much natural moisture your garden receives and how much supplemental water you plan to provide will significantly assist your decision-making process and reduce the Paradox of Choice predicament.
Celebrate Perennial Gardening Month by discovering new perennials or rediscovering your favorite classic perennials at your local garden center.
