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To continue with the theme of fall-blooming perennials established with my article about chrysanthemums, I’d like to talk about goldenrod. There are several species of goldenrod within the genus Solidago, most of which are native to North and South America. The genus name Solidago comes from the Latin word solidus, meaning to make whole, and is a reference to the medicinal uses of Solidago that were a common practice among many Native American tribes. Perhaps the most familiar species of goldenrod is Solidago canadensis, which is native throughout much of Canada and the United States. This species of goldenrod is a herbaceous perennial with arching branches and grows to a height of 2 to 6 feet tall, with a width of about 4 to 6 feet. The characteristic golden yellow flowers begin to emerge in August and last through October. As the blooms conclude, brown seed capsules covered in whitish-gray hairs develop. Goldenrod has been unfairly maligned as an allergen because of the vague similarity that these seed capsule clusters have to bloom of ragweed, blown pollen of ragwort, and other high allergen plants. In fact, goldenrod produces pollen that is much denser and damper than the light windblown pollen of ragwort and other high-allergen plants, and therefore isn’t particularly of concern in that regard. It is, however, a favorite of bees and other pollinators, and an important one at that, as there are relatively few pollen and nectar sources in the fall compared to spring and summer.
Top left: ‘Fireworks’ is an especially popular compact cultivar and diminutive species of goldenrod. Bottom left: Solidago flowers and leaves. Photo: David J. Stang, CC BY-SA 4. Right: The most familiar species of goldenrod is Solidago canadensis. Solidago rugosa, or rough goldenrod, is a slightly more compact species, growing 3-4 feet high and wide. The common name, rough goldenrod, refers to the stems lined with stiff hairs. For many gardeners, this compact form is a bit easier to find space for in the landscape, and the floral impact is just as substantial. The cultivar ‘Fireworks’ is especially popular, and is even more diminutive, at about 2-3 tall and wide. The flowers radiate in all directions and resemble a burst of fireworks, hence the name.
All species of goldenrod are fairly adaptable, but prefer full or mostly sunny conditions and average soil. The plant will, however, tolerate drought and low-fertility soils. It can be used in the landscape in natural areas, native gardens, pollinator gardens, and as a companion plant to other fall-blooming plants such as mums and asters. Compact cultivars such as ‘Fireworks’ can be used in edging pathways, in the front of perennial borders or foundations, and even in large containers. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705.
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Autumn is approaching quickly, and one of the landscape plants we most commonly associate with the fall is the chrysanthemum, frequently referred to simply as 'mum.' Fall flowers are often in short supply, compared to the relative abundance of blooms in spring and summer, and yet reliably year after year, chrysanthemums are the shining star of fall landscapes with their late-arriving blossoms. Chrysanthemums are short-day blooming plants, meaning their bloom is triggered by the shortening length of daylight and increase in length of darkness that occurs each fall. They are members of the Asteraceae, or daisy, family, with flowers resembling the classic disk-shape we associate with daisies. Many of the mums we buy and plant in the fall are herbaceous perennials, though gardeners treat them like annuals, ripping them out after the flowers have succumbed to frost.
Though there are several different types of chrysanthemums, and thousands of cultivars, all of the mums we use in North Carolina like essentially the same conditions, preferring well-drained, high organic matter soils in full sun. They will do okay in a small amount of shade, too, and an hour or two of late afternoon shade may even be a good idea, but more than that will reduce the amount of blooms you see. Mums do use a fair amount of water, particularly large, container-grown mums, but they don’t like to be in wet soil, so adequate drainage is quite important. If you’re planting mums this fall and want to overwinter them, you will need to do a bit of work in the spring and summer to duplicate the show you get in year one. Container-grown mums are pinched back repeatedly throughout the growing season in order to develop large dome-shaped plant shapes and they will need to be pinched back that same way in subsequent years in order to grow to the same size and shape the following year. Even the so-called hardy mums, which are treated more like traditional perennials, including cultivars such as ‘Sheffield Pink’ and ‘Mary Stoker,’ should be pinched back for peak performance.
Use mums in your landscapes in containers or in the ground, in lining walkways, edging along the front of a border area, or along a wall or other high-visibility areas. Mums can also be used as companion plants with asters, ornamental kale and cabbage, and other plants that stand out in the fall. Mums can develop some leaf spot fungal diseases, but avoiding watering the foliage and instead directing water to the root area of the plants will lessen those issues.
While mums have relatively low toxicity, there is an oil in the leaves and flowers that can cause redness and irritation in some individuals sensitive to the compound. There is also a natural insecticide made from an extract from chrysanthemum flowers and seeds. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. North Carolina has some truly fantastic native plants and there are great reasons to use these native plants in our landscaping. Native plants are part of our national heritage. Many serve as host plants and/or food sources for beneficial insects and wildlife, while many are simply attractive plants that are not often used in modern landscapes. Plants that are native to the United States, or North Carolina in particular, are naturally well adapted to our local conditions and tend to do well in our landscapes provided they are grown in conditions that mirror where they are found in nature. If incorporating natives into your landscape, use them wisely and with a proper amount of consideration. Remember that the conditions in our landscapes are often quite different than those a native plant might grow in naturally. For example, you’ll often find dogwoods growing naturally on the edges of forests, where they receive a good deal of shade, yet many people plant them in full sun in their front yard. Many other native plants grow naturally in wet, swampy areas but when used in the landscape, are planted in dry, sandy soil. Native plants, like any other, are subject to the 'right plant for the right place' rule, meaning that you should pick a plant that will thrive in the conditions you can provide for it. Any plant, whether native or non-native, that is growing in a less than ideal location is going to struggle. Simply knowing that a plant is native to North Carolina doesn’t tell us enough about that plant to make an informed decision on how to use it in the landscape. 
Above left: Close-up of flower, photo by Jim Robbins. CC BY-NC-ND 4.0 Above right: The flower, photo by Marcia Boyle CC BY 4.0 One underappreciated native tree that I particularly like is the Carolina silverbell, Halesia tetraptera. This is a medium-sized, multi-trunked deciduous tree that grows up to 30 to 40 feet tall, with a slender upright growth habit. Its greatest ornamental trait is its powerful spring bloom, with white, bell-shaped flowers that hang from the branches for a few weeks in April. Flowers emerge just before the leaves, which allows its bloom to have great impact. Silverbell attracts hummingbirds, bees, and a number of different butterfly species. It has dark green leaves that fade to yellow in autumn and drop early, revealing a small brown fruit that has some unique ornamental appeal. Carolina silverbell likes moist, slightly acidic, organic soils and grows well in mostly sun or light shade environments. Carolina silverbell is in the Styracaceae family, related to Styrax americanus and Styrax japonicus, the American and Japanese snowbells. Each of these is more commonly used in modern landscapes, and the American snowbell is, of course, a native as well. While the snowbells are small trees, 10-25 feet tall, and thus easier to fit in most landscapes, the ornamental features are quite similar to the Carolina silverbell. If you’ve got room in the landscape and the right soil and light conditions, Carolina silverbell would be an interesting plant to add. You probably won’t see at any other house on the block. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705.
Since we’re now in September, it's time to start thinking about pumpkins. My wife recently had me bringing fall decorations out of the attic, so pumpkins are fresh on my mind. You can probably find the pumpkin of your dreams at a local farm, but perhaps next year you’ll want to grow your own. If so, here are some things to consider. Both pumpkins and gourds are members of the cucurbit vegetable family. This means they are relatives of squash, cucumber, watermelon, zucchini, and cantaloupe. As such, they share many of the same pests, and many of the same soil and growing conditions. However, while most of the other cucurbits are used as food, pumpkins and gourds are primarily (but not solely) grown for their ornamental value.  Above: At a hefty 1,097 pounds, this pumpkin grown in Nash County won the 2023 NC State Fair’s contest for largest pumpkin grown by a NC resident.
If growing either pumpkins or gourds, be prepared to provide a good deal of space, as both are vining crops that will run 4-8 feet or more in each direction. Don’t overcrowd the plants. Avoid using sprinklers or other watering methods that wet the leaves, as foliar diseases will occur when leaf moisture is high and air circulation between plants is poor. Pumpkins and gourds will use a lot of nutrients during the growing season, so test your soil prior to growing, and follow recommendations. Fertilizing with too much nitrogen is a common mistake that will result in lush vine growth with few fruit. Harvesting pumpkins and gourds can be a bit tricky for beginners. For gourds, look for a change in the sheen of the skin. When mature, it will go from shiny to somewhat dull. You also want the outer skin to be hard and not easily scratched with your thumbnail. Pumpkins will also develop a more robust outer shell when mature and will be a deep orange color (for most varieties, anyway). Perhaps the most important thing to remember when harvesting your pumpkins and gourds is to cut through the stem with a knife rather than trying to twist or tear it from the vine. If the stem is damaged during harvest (or after), it will lead to a rapid decline in the post-harvest life of the fruit. Gourds and pumpkins with long intact stems are easier to handle and last much longer. Now, for the fun part: What varieties can you grow? There is a tremendous amount of variation in the color, shape, and size of pumpkins and gourds, much too many to list, but that diversity lends itself to their decorative uses. If you’re picking a pumpkin to turn into a Jack-o-Lantern, you will likely want one that is large, orange, and relatively smooth. If you’re using pumpkins or gourds for other decorative purposes, however, a good rule of thumb seems to be that the uglier and more unusual they are, the better they work as decorations. Many varieties are odd shaped, have weird growths on them, or come in random combinations of colors that look like an artist has splattered paint on the flesh of the fruit.
Some of the most interesting ones I’ve come across are ‘Red Warty Thing,’ a large pumpkin that looks exactly like the name, and ‘Porcelain Doll,’ a creamy-pink, flat pumpkin that is wider than it is tall. Comb through your favorite seed catalogs and find the ones that appeal to you. Grow a few favorites for next year!
Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. It seems like every year, in late summer or fall, after a wet period, the same thing happens: Mushrooms start to pop up in lawns and gardens. Without fail, the phone calls start, with caller after caller wondering why the mushrooms have shown up and what can be done about them. The simple answers to those questions are that the mushrooms appear because it’s wet and there’s nothing that you can really do about it, but there’s, of course, a little more to it than just that. Mushrooms usually arise in the lawn or garden when there is a type of fungus present in the soil and moisture conditions are high. Even though we don’t see it, there are always things happening inside the soil, and one of those things is decomposing of plant tissue, whether it be roots, stems, or fallen leaves that have incorporated into the soil surface. As this plant tissue breaks down, it becomes a food source on which mushrooms can grow and thrive. They are particularly prone to develop in areas where trees have been cut down, as the rotting roots underground contribute to mushroom growth. This can happen even several years after a tree has been removed.
Although there are many different types of mushrooms that show up in lawns, there are a few that are particularly distinctive. One is the stinkhorn, a foul smelling orange-mushroom. It is often long and slender and may have a dark tip. As with most mushrooms, much of its body is underground, so just removing the part that’s visible above ground won’t accomplish much. The mushrooms that result from fairy rings, a specific fungus that causes mushrooms to appear in circular patterns, are also distinctive. This disease is often particularly worrisome to those who have it, because of the unique pattern; however, it’s really no different than what I’ve already described. Decaying material in the soil feeds the mushrooms and they grow when there is a lot of moisture present. The growth just happens to be in a recognizable shape rather than random or scattered throughout the lawn.  Above: A fairy ring, the name given to mushrooms growing in a circle in grass.
Though not a mushroom, slime molds are fungi that also grow on decaying organic material under wet conditions. These often show up in flower beds where hardwood mulch is used. Slime molds can be quite unpleasant to look at. One slime mold is called dog vomit fungus, because that is exactly what it looks like. Although unsightly, this fungus won’t harm plants and can be eliminated by removing the mulch it grows on. Many mushrooms are nothing more than a nuisance in the lawn and garden. They can be mowed or picked, but will return as long as conditions stay wet. You may notice them in low-lying areas or others in poorly drained spots where extra water seems to collect. Improving the drainage or diverting water away from these locations might help with long-term mushroom control. Digging them out and replacing the soil in areas of heavy infestation is also an option, but probably one that would only be practical in very small areas. Herbicides such as roundup are not effective on mushrooms. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. Boxwoods are one of the most popular landscape plants in North Carolina. Well-maintained boxwoods can provide a landscape with a formal, elegant look. However, boxwoods are not immune to insect and disease problems. In fact, one might argue that they have more than their fair share.  Above: Create a formal, elegant look by shaping boxwoods into a circular profile. Below: Boxwoods sculpted into topiary forms.  Those of you who grow boxwoods, particularly the American type (although the English and Japanese are susceptible as well), may have seen damage caused by an insect called boxwood leafminer. The symptoms of boxwood leafminer injury include smaller than normal leaves with yellow blotches covering the top part of the leaf. The bottom of the leaf will be bumpy and blistery, as the leafminer has laid its eggs inside the leaf. Gradually the insects will hatch from the eggs and chew their way out of the leaf. The adult insects then puncture the underside of the leaf and lay eggs back into it. In addition to making a healthy boxwood quite unattractive , these insects are difficult to kill. Adult leafminers are active in mid-April, searching for new leaves to lay eggs in. If needed, this is the best time to treat with a contact insecticide, though they can also be treated with preventative systemic insecticides throughout the year. As always, follow the label directions if using an insecticide.
Above left: Yellow blotches, caused by the boxwood leafminer insect, form on the top part of the leaf. Above right: The bottom of a leaf infected by boxwood leafminers is bumpy and blistery.
light brown color. Once this happens, there is nothing you can do to save the plant, and you should not replant boxwoods in the same area, as they will be likely to develop the same disease, as it is permanently in the soil. Phytophthora is worse in poorly drained soils, so taking steps to improve drainage, such as adding compost or sand to clay soil, may be helpful as a preventative measure.
One of the most common problems of boxwoods is neither an insect nor disease but rather a physiological problem. Many types of boxwoods, particularly the Japanese types, tend to turn a bronze, orange, or reddish color during the winter. Not all leaves will turn this color, perhaps just a few on the tips of branches. This is normal and is caused by winter winds and may be worse when the soil is dry, the pH is too acidic, or if the temperatures vary drastically during the winter. This will generally not kill the plant, but will definitely make it less attractive. In the spring the new foliage often returns to a normal green color. Keeping the plants moist and adjusting the pH to about 7 by adding lime will lessen this type of winter damage. Boxwoods of all types tend to perform best in soils that stay on the dryer side, and in areas of partial to even full shade. As is often the case with landscape plants, planting the right plant in the right place is perhaps the most effective way to limit future problems. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. Over the last month, we’ve had quite a shift in our weather, from extremely dry throughout all of June to quite wet in July, with more rain from Tropical Storm Debby. Plants need water, of course, and since this wet period followed a month of dry weather, initially this moisture was quite welcome. However, too much rain all at once can cause some complications in gardens and landscapes. Let’s talk about a few of these complications. One of the things you commonly see in gardens following a period of wet weather is an outbreak of fungal diseases such as leaf spots and root rots. Leaf spots generally develop when the leaves remain wet for a longer than usual period of time. Root rots can be a problem for a wide variety of plants in poorly drained areas, such as heavy clay soils, or in low spots in the landscape where water pools. Another thing you’ll often see is a surge in mushroom growth. Mushrooms arise in the lawn or garden when there is a type of fungus present in the soil and moisture conditions are high. Many mushrooms are nothing more than a nuisance in the lawn and garden. They can be mowed, picked, or dug out, but will often return if the conditions stay wet. You may notice them in low lying areas or other poorly drained spots where extra water seems to collect. Improving the drainage or diverting water away from these locations might help with long-term mushroom control.
Above left: Leaf spots on Black-Eyed Susans. Above right: Mushrooms popping up in lawns following heavy rainfall. All photos in this blog: Susann C., Extension Master Gardener Volunteer, Pitt County Arboretum.
Many weeds can grow in more adverse conditions than desirable plants, so while your trees, shrubs, and lawn struggled during the dry period in June, many weeds quickly filled in the gaps and then took over once the big July rains came. When the weather is hot, it can be pretty tough to get motivated to pull weeds out of the dry, hard ground.
Now that the ground is soft, however, it’s a perfect opportunity to reclaim some of those out-of-control spots by pulling weeds. It’ll still be a little bit of hard work, but even the deepest-rooted weeds can be pulled out relatively easily after this much rain. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. Watermelons are a favorite vegetable for many gardeners. They grow on fast-growing vines that cover a large area of the garden. At this time of year, watermelons should be at or close to maturity, depending on planting date and management or environmental factors (such as how much rain you got compared to other parts of the county). Watermelon is related to cucumber, pumpkin, and squash. It shares many of the same pests, though they don’t necessarily affect each plant in the same way. Watermelons seem a bit more pest-resistant than those other family members in many cases. Insect problems are limited mainly to aphids and cucumber beetles, and diseases include powdery mildew and various wilt and various leaf spot diseases. Aphids are small, soft-bodied insects, usually yellow, green, or white. They are found on the underside of leaves, and secrete a substance called honeydew that makes the leaves appear shiny and wet. Aphids generally do little direct damage to watermelons, although they may carry viruses that can be very damaging indirectly. They should be sprayed with insecticidal soap. It is important when spraying to cover the underside of the leaves where the insects are found. Cucumber beetles have black and yellow stripes or spots. They also may carry diseases, and the cucumber beetle larvae can damage the plants by boring into the stem, causing the plant to die. Cucumber beetles can be treated with bifenthrin.
Powdery mildew is a disease that causes white fungal patches on the leaves of watermelon vines. The fungus spreads and eventually leaves die, causing the fruit to be exposed and ripen prematurely. Control for this is to plant resistant varieties and to avoid watering the leaves of the plant directly, especially during the day. There are a number of other diseases that may cause wilt or leaf spots that are a large concern for commercial growers, but are generally not a problem for home gardeners. If you do have a problem with watermelons, bring a sample to the cooperative extension office for identification.
 Since watermelons are 95% water, they need adequate rainfall or irrigation to mature properly. Lack of water can stress the plants, which will make them more susceptible to the problems listed above. A good rule of thumb is to provide the plants with about an inch of water every week. They also need a good dose of 10-10-10 fertilizer, and some supplemental calcium to ensure they don’t succumb to blossom end rot.
Luckily, weeds are not usually an issue for home gardeners growing watermelons. Many vegetables can be overtaken by weeds before even getting started, but watermelon vines grow so quickly they normally cover up weeds that would compete with less vigorous plants. Watermelons are generally ready to harvest once the stem begins to turn brown and twist, and the white spot on the bottom of the melon where it contacts the grounds has turned to yellow. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. Although new plants are introduced into the landscape trade each year, there are some plants that have been a part of our landscapes reliably for years on end without ever falling out of favor. There's something familiar, even comforting perhaps, to have such consistency in our gardens. One such plant is the crinum lily, an amaryllis relative, that performs admirably in a number of landscape situations throughout the southeast.
lily-like flowers. Flowers are typically some shade of pink, red, or white. The cultivar 'Milk and Wine' is particularly notable for its lovely pink and white striped blossoms.
Crinums can tolerate a bit of shade, but will bloom best in full sun. They tolerate a wide range of soils, and are fairly drought tolerant, though they prefer to have adequate moisture and good drainage. Newly planted crinums may take a year or two to settle before they bloom. As the plants age, the bulbs will produce offsets, and thus clusters of bulbs can be divided every four to five years or so. This provides ample opportunity to fill in empty spaces elsewhere in your landscape or share plants with friends. Dividing is best performed during winter months, though it can be done at other times of the year with reasonable success. The deep-throated blossoms on crinum are favorites of hummingbirds and butterflies, so one could easily incorporate crinums into a pollinator-themed garden. Crinums are particularly attractive when planted in mass plantings, but also work well as edging or in borders.
Crinums have a few minor pest problems, but are generally quite easy to grow. They are remarkably salt tolerant, which makes them ideal for planting closer to the coast, but also makes them well suited to be planted near roads and driveways. They are mostly deer resistant, likely due to the fact that all parts of the plant are mildly toxic, causing occasional gastric upset if ingested.
Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension?s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. Images are from the NC State University Extension Gardener Plant Toolbox at https://plants.ces.ncsu.edu/plants/crinum/ Peaches are one of my favorite fruits to eat during the summer. It’s really hard to beat the flavor of a fresh peach picked just that day. Unfortunately, growing peaches is unfortunately not as easy as one would hope, due to a variety of disease and insect problems, as well as a danger of ill-timed frosts that reduce yield. Peaches are native to China but have been grown in the Southeastern United States since the early 1900s. Like most fruit trees, they are normally grafted to ensure consistent quality. Trees developed from seedlings generally produce lower quality fruit.
Peaches need eight or more hours of daily sunlight, protection from late spring frost, and regular pruning to produce fruit. Avoid planting near the edge of a wooded area or at the bottom of a hill, as these areas carry an increased risk of frost injury. Peach trees grow best when trained to grow in a vase shape. Young trees have their central trunk pruned off early, leaving the tree with 3-4 strong lateral limbs, and an open center allowing for ample sun penetration. Yearly winter pruning helps maintain the open center. Once the tree is mature enough to produce large amounts of fruit, it is a good idea to thin the fruit each year. Fruit thinning means removing some of the flowers or young fruit early in the season to lesson the total number of fruit produced, but increase the size and quality of those that do mature. Mature peach trees often face the problem of branches bending or breaking due to heavy fruit load. Thinning helps reduce this problem, and also helps limit disease problems by creating more space between fruits. A properly thinned tree should have peaches growing about 6 inches apart on the stem.  Above: The showy flowers of a peach tree in bloom appear in spring, followed by fruit in summer. Photo: Jim Robbins CC BY-NC-ND 4.0 Those who wish to grow peach trees also face the risk of some disease and insect pests. Brown rot is a common disease of peaches and, like the name implies, causes peaches to rot and turn brown before they reach maturity. Fungicide applications during and after bloom can help reduce this disease, but it is also a good idea to remove damaged fruit from the tree and the ground around it in order to minimize spread of the disease. Insect pests include plum curculio, oriental fruit moth, and peach tree borer, of which peach tree borer is the most damaging. The insect bores into the stem, causing an orange-brown gel to accumulate around the trunk. Peach tree borers often affect trees that are already stressed, making it difficult to control.
Because of these issues, life expectancy of a peach tree is somewhere in the neighborhood of 15-20 years. Growing good peaches is not easy, but the reward that a well-cared for tree provides is tough to beat. Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center. If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705. |
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