As the blooms of perennials start to fade, it is time to deadhead to encourage blooms to continue throughout the remainder of the summer months. Deadheading rejuvenates a plant’s appearance, delays the plant from going to seed and redirects the plant’s energy into root and vegetative growth. Most gardeners practice pruning to keep plants tidy and to extend the bloom period of certain perennials.
With perennials that produce several stalks of flowers above the foliage, such as Salvia (Meadow Sage), prune the center (oldest) stalk and leave the remaining two side stalks to produce new buds and blooms. For a visual, observe any three fingers on your hand that are next to each other. When you prune your salvia you will be cutting out the center stalk that is done blooming. On each side of the center stalk you will see two other (lateral) stalks with new buds emerging and blooms forming. If there are blooms done on the two side stalks you can cut those out as well. Only cut the spent stalks and the new flowers will form. I usually get about three blooms out of my salvia throughout the summer and into the early fall.
For Veronica (Spiked Speedwell), blooms start from the bottom of the stalk and work their way up. In the early stages of growth, the blooms will appear to be colorful on the bottom with green tips on the top of the stalk, making for very nice contrast! As the blooms mature, the entire stalk will be one color (mainly blue, purple, pink or white). Remove the spent blooms once the entire stalk has faded and the plant will produce new stalks and blooms to keep the interest coming. Deadheading will also encourage new light green foliage to emerge from the plant.
Daylily benefit from deadheading of faded blooms and removal of entire spent flower stalks. In mid-summer, when your daylilies are completing their first major bloom and producing seeds, remove faded flowers and seed stalks so that the plant’s energy goes back into producing new blooms. Clean up the appearance of the plant by removing any browned foliage, which usually can be seen around the base of the plant. While removing seed stalks will encourage more blooms, removing spent foliage will encourage new growth to rejuvenate the plant.
Other perennials that benefit from deadheading include, but are not limited to, Dianthus, Bee Balm, Lavender, False Sunflower, Coneflower, Yarrow, Blanket Flower, Butterfly Weed, Shasta Daisy and Aster.
By the second or third round of blooms, you may want to feed your plants to give them a boost and add energy for the rest of the season. (Note: Be sure not to feed in extreme heat as it can stress them, but rather wait for cooler temperatures). If your plants are brand new they may have been force bloomed, so for the first season you may only get one or two blooms, but come next year you will be able to push out three blooms on some plants if you time your pruning right. With regular maintenance of your perennials you can benefit from continuing blooms throughout the season.
Have the temperatures been rising and are you yearning to go out into the garden? Spring is here and it is a time to start planning and prepping the garden for a successful start to the planting season. There are some recommended maintenance tips for getting your garden underway. Here is a list of common gardening tasks to be performed in late winter/early spring. (I recently posted this article on my other blog A Guide to Northeastern Gardening, but felt it was also fitting for here.)
True or False? Any dead material remaining from last year should be removed from your garden now. True. It is best practice to remove dead material from the garden in fall to prevent possible pests and disease in your garden. If you have left annuals or perhaps perennials for winter interest, now is the time to tend to them, along with any weeds that might have survived the winter. Pull out any dead remaining annuals and prune perennials back to the ground to encourage new growth. If cold temperatures are still to be expected, push mulch up around the crown of the plants to protect them from temperature fluctuations.
True or False? New mulching should be applied now before the ground thaws.False. Mulch acts as an insulator and applying mulch before thawing would actually inhibit warming as temperatures rise. Allow the soil to warm, then apply two to four inches of natural pine mulch. When applying, keep mulch several inches away from tree and shrub trunks to prevent oxygen loss and rotting. Mulch benefits plants by reducing water evaporation, preventing weeds, adding organic matter to the soil and also acts as a buffer, preventing drastic changes in soil temperatures.
True or False? Nitrogen based lawn fertilizer can only be applied after April 1st. True. According to the EPA, the prohibition on application of fertilizer between December 1st and April 1st applies to products that contain nitrogen (N), phosphorus (P), or potassium (K). If a product does not contain any of these nutrients, it could be applied during the winter months without violating this law. Explanation: If the ground is frozen, there is a greater danger of runoff and possible contamination of groundwater. Fertilizers applied when the ground is thawed and porous are absorbed and utilized by plant material and go through a natural filtration process before reaching the aquifer system. Please note that there are a variety of organic, natural fertilizers on the market that are more environmentally friendly. Success rate depends on brand and application.
True or False? Spring flowering trees and shrubs should be pruned in late winter/early spring. False. General rule of thumb is to prune flowering plants AFTER they flower. Early spring flowering trees and shrubs including rhododendron, azalea, forthysia, magnolia, plum, Eastern Redbud and cherry form their buds from the season before and should be not be pruned until after flowering. Pruning them now will remove flower buds that have already formed, resulting in a loss of blooms.
True or False? Summer blooming shrubs such as Spirea and Buddleia should be pruned in spring. True. Mid and late summer flowering shrubs such as Spirea and Buddleia (butterfly bush) prefer a spring pruning to promote fullness and blooms. Prune Spirea slightly for shaping. If the plant is overgrown to the point it is unsightly, it can be pruned more drastically to rejuvenate it now in spring. Buddleia benefits from an early spring pruning and should be pruned all the way back in late winter/early spring to promote fuller plants and better blooms in late summer. This practice is best performed once you see signs of life on your plants.
True or False? The best time to prune evergreens is in early spring. True. Evergreens can be pruned anytime when there is no threat of extreme temperature changes that would cause undue stress; however, the best time is either in early spring before they push out new growth, or afterwards once new candles form. When pruning evergreens that form candles, such as white pine, it is best to cut candles in half to keep the plant more compact.
True or False? Liriope and grasses should be cut back and divided now in spring. True. Liriope and ornamental grasses can be cold sensitive. Exposing the crown of the plant could be the reason for snow and cold damage. It is best to leave liriope and grasses alone in fall and to prune them back in early spring to allow for new growth. Spring is also the time to divide and move other perennials that have become overgrown. It is recommended that most perennials be divided every four years for best bloom. Dig up and divide with a sharp clean spade just as new growth appears, replant and add a sprinkle of slow release plant food in with the soil to help root promotion. Water in thoroughly.
True or False? Knock Out Roses should be pruned back in early spring. True. Wait until your roses are sprouting new shoots and showing some signs of life. Then, prune off dead wood or overgrown branches back about one third the size of the plant to promote strong growth and blooms. Be careful to watch while pruning so that you achieve a nice rounded shape for your plant. Early spring is also a good time to apply an organic slow release rose fertilizer mixed in with the soil at the base of the plant to ensure a successful start to the growing season. I would also recommend a regular watering schedule from the base of the plant, since roses do not fair well with constant water on their foliage.
True or False? Summer blooming bulbs should be planted in late spring. True. While spring blooming bulbs such as crocus, hyacinths, tulips and daffodils are planted in fall, late summer blooming bulbs such as Dahlia, Canna and Gladiolus are planted in spring. Amend the soil with compost or manure to insure them a good start and plant in a well-drained area to prevent rotting. Generally, bulbs are planted at a depth of three times their diameter, and specific instructions are usually supplied on the packaging. Once planted, water your bulbs thoroughly and be sure they get watered regularly. Applying bone meal will give your bulbs energy during the growing season, but do not mix in too closely to the roots.
Will the unpredictable weather we have been having across most of the U.S. and other areas harm my garden? I have been getting asked this question quite a bit over the past couple of years. Generally, plants are pretty resilient. Buds that are forming on the trees early are sparked by the warmer temperatures in daytime but slowed down by the colder nighttime temperatures, which tends to balance out their progress. If there is severe cold for a prolonged period of time, buds could freeze and get damaged, but the tree produces enough buds to still have a bloom. More sensitive plants like old fashioned hydrangea ‘Nikko Blue’ that bloom on old wood are more susceptible to cold and time will tell. If there is die back on your plant, prune out the dead wood and apply a dose of a high phosphorus fertilizer. It could help to boost larger blooms from any undamaged buds. Hydrangea varieties that bloom on new wood, such as ‘Endless Summer’ and ‘Pee Gee’ should winter alright.
Some of my evergreens are a bronze color. Should I be concerned?Winter bronzing is normal on evergreens near the end of winter while temperatures are cold. Once the temperatures rise and new growth is stimulated, the foliage will turn back to a more vibrant green. Broken or dead branches are different in that they are completely dried out and brown. Those branches should be pruned off the tree in late winter/early springtime to prevent any further damage. Any falling or divided tree leads can be arbor tied to secure them and encourage upright growth. Split branches can also be arbor tied together, and if caught in time the cambium growing layer of the tree can mend. In the photograph above, the center upright Western Arborvitae are displaying bronzing and there are no signs of broken branches. As you can see the trees are healthy.
Have you heard about my new book,Landscape Design Combinations? My first bookA Guide to Northeastern Gardening covers recommended plants for zones 3-9 with topics including butterfly gardening, deer resistant plants, shade gardening, perennials, trees and shrubs, evergreens, general maintenance tips and more.
Landscape Design Combinations is a continuation of the previous publication, with greater emphasis on design, including numerous numbered and labeled photographs of successful landscape plans. Topics include elements of landscape design, designing for the seasons, how to build a natural stone patio or walkway, simple container combinations and garden styles throughout the centuries.
Both A Guide to Northeastern Gardening and Landscape Design Combinations were written to provide you with the tools needed to help you to create a successful garden. Click on the links below for more information and previews. I hope to inspire you!
It has been a busy Sunday afternoon in August with the summer temperatures starting to cool and a cooler than usual September in the forecast. I took the time today to give the garden a face lift and rejuvenate some of my fading perennials. By the time late July and August roll around various perennials are starting to show signs of fall mode with yellowing and dying foliage as they are starting to go dormant. Perennials such as daylily go dormant at the end of summer into fall but there are methods to extend the bloom time right into mid to late September. With certain species of long blooming daylily such as ‘Stella D Oro’ there is a trick I learned initially by accident.
I had some late summer garden maintenance done a few years ago and the crew had cut the yellowing daylilies back to about four inches from the ground. At first I was taken by surprise but within a couple of weeks I had brand new vibrant green foliage and blooms that lasted well into fall. From that time on I continued to follow this ritual of cutting back my lilies starting at the end of July and into mid-August so that I could enjoy constant blooms. The procedure is quite simple and I stage the rejuvenation at different times for the various locations of lilies in my garden. Starting at the end of July and into late August I carefully remove expired yellowed foliage on my perennial daylilies down to new growth which is approximately four to five inches above the ground. I actually perform this by hand but you can also use pruning shears and if there are any blooms on the plant you can leave them to enjoy. This ritual of removing dead foliage stimulates the plant to produce healthy new leaves and blooms and also prevents the onset of fungal disease that can occur at this time of year with decaying foliage.
I also remove the expired scapes (bloom bearing stalks) from the plants as soon as they turn brown throughout the entire season which stimulates new blooms. The photograph on the left shows how the stalks should appear when you remove them. It is easy to know when this should be done since the stalks with seed heads will very easily pull out without any effort. The photograph on the right shows newly cut foliage right after rejuvenation. Once your daylilies are cut back be sure they continue to receive watering. In no time you will have plants that appear as they do in early spring bursting with beautiful new growth and flowers. Once the plants have had their final bloom into the fall allow the foliage to die completely back and then remove any decaying debris from around the plant and apply a thin layer of mulch.
This method also works with other varieties of daylily with a shorter bloom time such as ‘Pardon Me’ and ‘Sammy Russell’ but should be performed in July after these plants are done blooming. Other perennials such a Salvia also benefit from a mid-late summer pruning which is explained in this article. If you are looking to extend the enjoyment of your summer garden rejuvenation is a simple and quick process well worth the time for it will prolong your enjoyment of blooms well into fall.
Salvia ‘Maynight’ is one of my favorite blooms in the garden with its vibrant deep purple flower spikes starting at the end of May and lasting throughout the summer with proper pruning. When your plants are starting to look a little less desirable then is time to dead head. It is sometimes difficult to explain how to prune salvia so follow me on this. Take a look at any three fingers on your hand that are next to each other. When you prune your salvia you will be cutting out the center stalk that is done blooming. On each side of the center stalk you will see two other stalks with new buds and blooms forming. If there are blooms done on the two side stalks you can cut those out as well. Only cut the spent stalks and the new flowers will form.
I usually get about three blooms out of my salvia throughout the summer and into the early fall. By the second or third bloom you may want to give your plants a little plant food to give them a boost and add energy for the rest of the season. If your plants are brand new they may have been force bloomed so for the first season you may only get one or two blooms but come next year you will be able to push out three blooms if you time your pruning right.
With proper maintenance you will get full enjoyment from your Salvia with blooms throughout the entire summer and into fall!