Fall Clean-up Tip: GRASSES: Cutting back ornamental grasses in fall can be harmful to them since freezing temperatures and cold snow lying on the crown on the plant can “hollow” them out. Grasses should be cut back in late March/early April once the threat of frost is gone and before new growth appears. If you want to tidy up your ornamental grasses, cut them back half-way in fall and leave the remainder of cutting back to spring. Leaving the grass during the wintertime also provides interest to the garden while preventing damage to its center.
The same technique should be used for maintaining Liriope (Lillyturf). Prolonged freezing temperatures can do damage to the crown of the plant, so it is best to leave the pruning until early spring when first signs of new growth appear.
Other ornamental grasses such as Japanese Forest Grass (Hakonechloa macra ‘Aureola’) die back in winter but do look attractive in the landscape The same principles apply and pruning is best when performed in late winter/early spring.
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!
After you have invested time and money into your landscape it is important to take proper care of your plantings. Here is a list that I have compiled over the years that I share with my clients. I hope you will find it useful!
WATERING: Water thoroughly after planting and keep well watered throughout the first growing season. Be careful not to over water! Feel down by the roots to determine whether the plant is getting the correct moisture. Soil should appear moist but not wet or overly dry. Consider type of soil, time of year and amount of sun and rain. Make sure fall plantings get enough water until the ground freezes in winter and then when the ground thaws. If you do not have a sprinkler system the use of soaker hoses is recommended. Water should be applied at a rate of 3/4 inch of water every three days or 1 1/2 inches a week. (One inch of water goes down 6 ” into the soil.)
GENERAL: Drip lines need to be run longer (2-3 hours) versus mist heads (30-40 minutes) Adjust accordingly depending on soil type, sun verses shade, etc. Water thoroughly and regularly the first growing season until the plant’s root system is established. Do not rely on rainfall alone. Do not rely on lawn sprinklers alone, as they may not supply an adequate amount of water. Watering by hand, two or three times a week to supplement your irrigation system is recommended in summer heat.
EVERGREENS: Most evergreens can be pruned at any time of year except when the weather is too hot or right before temperatures start to drop below freezing. Ideally the best time is believed to be in March before new growth starts. This also eliminates any winter burn that can occur during especially cold weather and gives the evergreen a good start for spring. Most evergreens will not take well to hard pruning. The only exception is Taxus (Yew) which may rejuvenate over time. No plant is completely maintenance free so keep your evergreens trimmed to their desired size. This will also keep them full and healthy and prevent thinning out. NOTE: Evergreens will shed their needles or foliage in the Fall/Spring to allow for new growth. If any branches appear brown or dead after planting or after winter, trim them off and allow the plant to rejuvenate. When in doubt ask a professional.
WINTER CARE: BROAD LEAVED EVERGREENS: Some Broad-Leaved Evergreens such as Cherry, Skip or Mountain Laurel, Japanese Aucuba, Holly and Rhododendron can be subject to winter burn from dehydration due to water loss in the case of a cold and dry winter. Care should be taken in the usage of an anti-desiccant such as ‘Wilt-Proof” Spray which should be applied around Thanksgiving and again if there is a thaw during the winter months. Do not apply when the temperatures are freezing.
FLOWERING SHRUBS: Prune flowering shrubs and flowering evergreens after the bloom (late August into fall) Flowering shrubs such as hydrangea bloom on the last year’s growth and will not bloom if cut back in spring. Shrubs such as Spirea improve bloom when cut back in Fall/Winter (March) before they get their leaves in spring. Renovate Lilac in winter and prune for shape after flowering in spring. Prune roses in spring to remove winter damage before new growth starts.
ROSES: Apply an all in one systemic feed and insect control into the soil around each plant such as Bayer All in One Rose & Flower Care a few times throughout the summer to keep your roses beautiful and insect free. Follow dosage on label. Deadheading on Knock Out Roses is not essential but doing so will keep your plants full.
TREES: Prune (or move) deciduous trees in fall after leaves have fallen and tree is dormant. Evergreens can be moved in either spring or fall and must be kept well watered.
GRASSES: Grasses should be cut back in late March before new growth appears. Leaving the grass during the winter provides nice interest to the garden.
PERENNIALS: Deadhead perennials such as salvia though out summer for continuous repeat blooms. In fall perennials should be allowed to die back then remove any unwanted foliage. Pruning back perennials can be done in either late fall or early spring (March) before new growth appears but it is recommended in the Fall in order to prevent disease. Note: There are some perennials such as liriope (lillyturf) and coral bells (Heuchera) that can provide nice winter interest and can be pruned back in spring.
FERTILIZING: Feed plants in spring and Late Summer. Do not apply a full dose if feeding in the fall. Apply a half dose for root feeding only. For new plantings allow the plantings to become established then apply a slow release organic fertilizer or apply a “starter” formula when planting. For established plants there are several products on the market. Be careful not to buy a concentrated product that will burn the roots. A slow release or organic fertilizer such as Holly Tone is recommended. Once again when in doubt ask a professional.
INSECT CONTROL: Periodically check your plants for insect or fungal damage and treat if needed. It is advised to use a regular insect control maintenance program to keep your plantings healthy.
LAWN CARE: Ideally sod lawns are best planted in spring and seed best planted in the fall. Core Aeration and over-seeding are best done in the fall to help rejuvenate a lawn and give it a healthy start for the following season. Your lawn should also have a regular maintenance program to keep it at its best ask your professional.
Ornamental grasses and various varieties of sedge are often used in landscape design in order to add grace and movement to a garden. There are a vast variety of plants to choose from so I will discuss a few of the more popular and widely used species that are all hardy in zone 7. Ornamental grasses and sedges can fit into a variety of landscapes including foundation plantings, poolscapes, perennial borders, rock gardens and naturalized settings, and as an added bonus, most are also deer resistant.
Dwarf Fountain Grass (Pennisetum alopecuroides ‘Hameln’) is an attractive dwarf grass growing to 2-3 feet in height and hardy in zones 4-11. ‘Hameln’ requires full sun and prefers a well-drained soil. It is drought tolerant once established. It is known for its wispy green foliage in summer and golden-rust foliage and fluffy, buff-colored plumes appearing in fall. ‘Hameln’ works nicely along with evergreens or flowering shrubs in a foundation planting or as a backdrop in a perennial bed. There is even a smaller sized variety of this grass called ‘Little Bunny’ which grows to only 1-2 feet in height and width for tighter areas. The grass is almost identical to ‘Hameln’ only the foliage and plumes are on a slightly smaller scale.
Miscanthus sinensis ‘Yaku Jima’ is a hardy ornamental grass in zones 5-8 and grows to 4-5 feet in height. It requires full sun and is drought tolerant once established. ‘Yaku Jima’ serves nicely as a backdrop in a perennial border or in a privacy screening. It also looks beautiful in a poolscape or pond planting. The beauty of this dwarf version of traditional Miscanthus is that is does not become top-heavy and flop over but rather remains upright throughout the season. .
Miscanthus sinensis ‘Morning Light’ is another form of upright grass with narrow green foliage edged in creamy-white. It is hardy to zones 5-9 and requires full sun to partial shade and grows to a height of 4-6 feet tall by 3 feet wide. Coppery-pink plumes emerge in fall. ‘Morning Light’ also serves nicely in pool settings and perennial or privacy borders along with evergreens. The variegation contrasts nicely with an evergreen backdrop.
Hakonechloa macra ‘Aureola’ (Golden Japanese Forest Grass) is one of the most attractive of the ornamental grasses and one of the few that prefers to be grown in shade Hardy to zones 4-9, Hakonechloa forms mounds of bamboo-looking grass growing to 6-8 inches tall by 12-18 inches wide. Japanese Forest Grass prefers a moist loamy soil and serves nicely in an informal setting such as a garden border or shade garden.
Carex oshimensis ‘Evergold’ (Variegated Japanese Sedge) is a grass-like Japanese selection forming low clumps only 6-8 inches tall by 9-12 inches wide. It prefers to be grown in part sun to full shade in a moist, loamy soil. Carex ‘Evergold’ is hardy in zones 5-9 and displays a green-yellow variegated foliage. It serves nicely in a rock garden, foundation planting or perennial border.
Carex ‘Aurea’ is another form of Carex displaying golden foliage and growing to a height and width of 2-3 feet. This Carex is hardy in zones 5-9 and prefers full sun to partial shade a moderately moist soil. Glowing yellow foliage has an edging of green and forms dense upright clumps which fit nicely into pond settings and in shady areas.
Imperata cylindrica ‘Rubra’ (Japanese blood grass) is often used in naturalized areas displaying its bright red-green foliage. Japanese Bloodgrass grows to a height and width of 12-18 inches and forms clumps that spread by rhizomes. It is hardy in ones 5-9 and prefers full sun to partial shade and a well-drained soil. This species of ornamental grass can spread easily so plant in an area where it can be controlled.such as the pool planter shown above.
Acorus gramineus ‘Ogon’ (Golden Variegated Sweet Flag) is not a true grass but has a grass-like appearance growing in dense upright mounds of bright golden foliage. Sweet Flag is hardy in zones 5-11 and prefer to be grown in partial sun to dense shade in a moderately moist soil. Mature size is 8-12 inches high by wide and Sweet Flag serves nicely in a pond setting, rock garden, or foundation planting as a ground cover under the canopy of trees.
The last grass, Miscanthus sinensis ‘Zebrinus’ (Zebra Grass) is known of its striking horizontally banded foliage. Golden-yellow bands on green fronds are displayed on this larger upright clumping grass that reaches a height and spread of 6 feet and up to 8 feet tall with plumes. Miscanthus sinensis ‘Zebrinus’ prefers to be grown in full sun to partial shade in a well-drained soil and is hardy in zones 5-9. Tiny pinkish-copper tassel-like flower heads form in late summer, gradually turning into silvery white plumes in fall. Flower plumes persist well into winter providing good winter interest. This plant serves nicely in an informal beach-like or coastal setting.
Depending on your landscape, ornamental grasses can add wonderful all-season interest to the garden and serve a variety of functions. There are so many varieties of sizes and foliage to choose from that they can fit into just about any type of setting.
Ornamental Grasses: Winter cold and snow can harm the center of ornamental grasses causing them to “hollow out”. To protect ornamental grasses such as ‘Miscanthus sinensis’ Maiden Grass or Dwarf Fountain Grass ‘Hameln’ avoid the temptation to cut them all the way back in Fall. Instead keep the roots well protected and wait until late March to early April to cut them back fully. If your grasses become a bit unruly by the end of Fall (November-December zone 7) then just cut back the plumes and leave the rest for early spring. Another trick is to wrap a bungee cord about half way up around the center and let the grasses drape over keeping them upright and in place. Ornamental grasses can add much interest to the winter landscape and be enjoyed all winter long. For more information visit: Fall-Garden-Maintenance-Pruning-&-Dividing-Ornamental-Grasses-and-Perennials