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Impatiens Downy Mildew
Impatiens Downy Mildew Symptoms

Impatiens Downy Mildew

Impatiens Downy Mildew is a relatively new disease problem for American gardens and now is being observed in many areas around the country. Rain and cooler night temperatures provide the perfect environment for disease infection. You may be experiencing early decline in your Impatiens.
Here is what you should look for:

Which plants get this disease?
This is a disease that affects all Impatiens walleriana plants (garden impatiens, including double impatiens). It does not affect New Guinea Impatiens
(I. hawkeri), SunPatiens®, and other bedding plants may be affected. There are other species that may get Downy Mildew.

Symptoms:
Downy Mildew symptoms on Impatiens typically start with a few leaves that appear slightly yellow or off color (not to be confused with lack of fertilizer), and become completely yellow over time. Leaves may curl downward as if they need to be watered. Under humid conditions, a white, downy-like growth develops on the underside of primarily yellow or curled leaves, but can also be found on the underside of green leaves. Sometimes it is difficult to see the spores without a magnifying glass. Eventually the leaves and flowers will drop, resulting in bare stems with only a few tiny, yellow leaves remaining. These stems can become soft and the plant collapses, similar to frost damage.
Impatiens Downy Mildew tends to be worse in:

  • Locations where leaves stay wet for extended periods of time (4 hours or longer).
  • Very dense plantings – plants spaced close together.
  • Gardens receiving overhead irrigation, because the foliage does not dry quickly.
  • Plants in heavily shaded areas where the leaves stay wet for extended periods of time.
  • Extended periods of rain and cool (below 65F) night temperatures. Much like we experienced in early September.

How it spreads:
Downy Mildew can be spread short distances by water splashing from infected plants and greater distances by wind-borne spores from infected plants in nearby landscapes. Impatiens Downy Mildew can occur in beds with no history of the disease if wind-dispersed spores blow in from other locations. Once plants are infected they will not recover. Fungicide applications by home gardeners are not recommended since effective fungicides are not Fungicides such as Mancozeb and Daconil are recommended for use as a preventative before the symptoms occur. It is best to rotate fungicides so that the disease does not build up resistance.

What to do with infected plants:
Plants with this disease should be removed, roots, soil and all, bagged and disposed of. Do not compost infected plants, as there is a high risk that this disease will overwinter and infect Impatiens in future years.

What to do next spring:
When deciding what to plant next spring in areas that are heavily shaded with very little air circulation, it would be prudent to choose an alternative shade solution. Alternative solutions that would perform well in shade include Caladiums, Begonias, Coleus and Torenia. These plants can all be safely planted in beds with a history of impatiens Downy Mildew. If you still want to plant Impatiens, it is best to select a site with good air circulation and morning sun to allow any moisture from overnight to dry.

Now that it's cooling off, pansies will provide a great replacement for color during cooler seasons. Additionally, you can plant Dianthus, Snapdragons, Dusty Miller or Ornamental Kale among other annuals. If you have any questions, be sure to visit one of our year-round locations and speak with one of our gardening experts.

Source: 

UMASS Extension, Center for Agriculture, "Impatiens Downy Mildew in Home Gardens"

Flat White Boer
Crunchkin
One Too Many
Jarradale
Peanut
Polar White

Heirloom Madness

Looking for a unique addition to your pumpkin patch, front porch or dinner table? Nowadays you are more likely to encounter unique pumpkin varieties that until recently were impossible to find unless found at a farmer’s market or your own veggie patch. From the slate-gray jarrahdale heirloom from Australia and New Zealand, to the warty peanut variety, many of today’s pumpkins are works of art even without being carved. And, most of these distinctive pumpkins are good for eating as well as good looking. So, before you pick up yet another round, orange orb, consider some of these fantastic heirloom pumpkin varieties:

Flat White Boer – a flat pumpkin with a creamy, white rind and thick, orange flesh. Flat white grows wider than tall and adds a distinctive look to any fall displayed. The sweet-tasting orange flesh is perfect in pies and for baking. This pumpkin keeps well and should last throughout the fall season.

Crunchkin - the hard shell version of the popular Munchkin, Crunchkin is flat-shaped with prominent ribs and a medium-orange color and slight flecking. Its hard shell gives it extended storage ability, making it a perfect choice for incorporating into tablescapes, fall floral arrangements, and outdoor displays.

One Too Many – the pumpkin that looks like a bloodshot eyeball, hence the name ‘one too many’. This 20 pound, round to oblong pumpkin has a white background accented with midribs and stippled veins of red. A truly distinctive ornamental pumpkin that has great decorative potential.

Jarradale – a medium to large (12-18 pounds), drum-shaped variety with heavy, rounded ribs and a distinctive slate-gray skin. The fine-textured flesh is golden-orange and sweet. Stunning in fall displays and great for eating too.

Peanut - a lightly ribbed, almost round pumpkin with a rich peach colored skin and a unique, bumpy covering that resembles peanut shells. The bumps are formed by sugars in the flesh, so, the more peanuts, the tastier the flesh is. Its flavorful, sweet-orange flesh lends good flavor to baked goods, soups and stews. Peanut pumpkins weigh about 10 to 20 pounds and make a real statement when added to fall displays.

Polar Bear – an extra-large, white pumpkin, lightly ribbed weighing 44 to 55 pounds with yellow-orange flesh. Great for carving, since their skin is not quite as thick as an orange pumpkin's. White pumpkins provide great contrast in fall gourd and pumpkin displays and its ghost-white exterior make it the perfect choice for Halloween.

Encore Azaleas
Rudbekia (Black-eyed Susan)
Asters
Russian Sage
Abelia Kaleidoscope
Fall-blooming Camellia, Pink-A-Boo
Fall-blooming Camellia, Hot Flash
Fall-blooming Camellia, Yuletide

Flower Your Fall Garden

Fall in Hampton Roads is one of the most beautiful times of the year offering vibrant colors and rich textures. And, there are plenty of dazzling annuals, perennials, and shrubs that provide colorful blooms that turn an otherwise boring yard into a flourishing fall garden. Here's a few of our top picks for the season to use in the landscape:

Encore Azaleas – if you love the colorful flowers that azaleas offer, then you'll love the Encore varieties. Encores bloom three times per year - summer, spring, and fall, yes, even fall! This repeat bloomer adds vibrant, multi-seasonal color unlike any other azalea and can grow to 2 feet tall and 2 feet wide or 5 feet by 5 feet, depending on the variety. Encores offer a wide selection of plant sizes and bloom colors from reds, to whites, to pinks and even corals. Perfect as a base plant, in container gardens, borders, as a foundation planting or in woodland gardens. Prefers well-drained soil and partial sun.

Rudbeckia - more commonly known as black-eyed Susan, this popular perennial is durable and easy to grow - a true sunshine worshiper that forgives neglect. Featuring 2 to 4 inch blooms with golden, yellow rays and a prominent purplish-black center cone, this long-blooming wildflower produces an abundance of blooms non-stop for most of the summer into early autumn. Rudbeckia is often massed together in borders and is also effective at erosion control. Flowers attract butterflies and the seed heads provide winter food for seed-eating songbirds. Thrives in most soils in full sun.

Asters - this perennial flower comes in all shapes and sizes from short and low-mounding to tall and willowy. Blooms appear in late summer into fall with charming, daisy-like flowers in pink, white, or blue and mostly bright orange or yellow centers. With a multitude of purposes, asters are a stunning addition to a wildflower garden, useful in a traditional border, or mingling in a rock garden. Grow in full to part sun in well-draining, moist soil with regular waterings, especially in the summer. Once established, asters are drought tolerant. A great choice for butterfly gardens.

Russian Sage - this tough, clumping perennial flaunts silvery foliage and sprays of small, lavender-blue flowers on up-right stems. Blooms appear continuously from late spring through summer. Its cool-colored flowers and foliage combine well with reds, oranges, and yellows, and its fine-textured foliage partners well with coneflowers, black-eyed Susan (Rudbeckia), iris, asters, and sedums. Taller varieties are great for the back of borders. Both heat and drought resistant, this perennial prefers full sun locations.

Kaleidoscope Abelia - you'll love this evergreen shrub all year, especially during autumn. Features variegated, bright yellow and green foliage and petite, white flowers during the warm season. In winter, foiliage changes to brilliant shades of red and deep orange. This low, compact selection reaches 2 to 2 1/2 feet tall and 3 to 3 1/2 feet wide and works well as a foundation plant, low hedge, mass planting or in patio containers. Abelia prefers partial to full sun.

Camellias - another wonderful shrub for the fall landscape that tops our list every year for fall interest. Fall-blooming camellias bring a splash of color to the autumn landscape when you need it most. These flowering shrubs not only offer beautiful blooms but feature glossy, evergreen leaves that bring a welcome touch of color to your garden. The varying bloom times, color choices and diverse mature size options make these a must-have. Fall-blooming varieties include Hot Flash, Pink-a-Boo, Shishi Gashira, Yuletide and Autumn Rocket, just to name a few. Camellias prefer moist but well-drained acidic soil and light shade in the summer with protection from wind in the winter.

The Fall Lawn
McDonald Garden Center Fall Lawn Kit

Now's the Time for Fall Lawn Kits

Check out the video to learn more about fall lawn kits:

Everyone knows that a lush, green lawn is a labor of love. To help you on your road to lawn success, we've developed an easy-to-use lawn kit specifically formulated for Hampton Roads.

Fall is the best time in our area to establish and repair the fescue lawn. During fall, soil temperatures cool down, so you'll get better germination and quicker establishment. And, the fall season typically delivers more consistent rainfalls, which also aides in establishment of new seedlings. Summer is the hardest season on fescue lawns, so planting in the fall allows for the longest time period before summer comes around again. Root development also occurs in the fall, which is vital when starting a new lawn.

Be sure to attend one of our complimentary grass classes held every Saturday, at 11am, now through October 13, 2018, at both our Independence and Great Neck locations.

Repotting Houseplants

Repotting Houseplants with Mike Westphal, the Garden Guru

Houseplants need occasional repotting for a variety of reasons that result in a healthier plant. The repotting process allows you to give the plant a more suitable growing environment with additional space and soil with appropriate nutrients. There are a few reasons why you may want to repot a houseplant; one, you may want to upgrade to a nicer pot, and two, the plant may be root bound. When a plant is root bound, the roots consume a majority of the pot and their root systems may not be able to derive the water and nutrients needed to support growth. Root bound plants can become restricted and the older leaves may lose their color and drop.

STEPS TO REPOTTING:

  1. Select your new container - choose a clean, new pot that is no more than two-inches in diameter larger than your plant’s old home. Too much space can slow growth and may lead to root rot.
  2. TIP: If your container doesn’t have a drain hole, place your plant in an inexpensive, plastic pot with a drain hole. Simply insert the plastic pot into your new container. The new container will act as the saucer and catch water.

  3. Choose a good, all-purpose potting soil – a good potting soil helps the plant to retain moisture, provide enough air for growing roots to be able to breath and not rot, and supports your plant by providing anchorage for the roots. Our McDonald Potting Soil is an all-purpose soil specifically formulated for Hampton Roads and is available in both traditional and organic formulas.

  4. Fill the pot with potting soil - fill the bottom of the new pot with one-to-two inches of potting soil and smooth out.

  5. Carefully remove the plant from the old pot.

  6. Gently loosen-up the plant’s root ball.

  7. Place the plant into the new pot and fill in around the plant with potting soil.

    TIP: lightly packing the soil around the plant will help to prevent air pockets and will also help to establish a good root to soil connection.

  8. Fertilize & Water - feeding is essential to keeping healthy plants. Unlike an outdoor plant, where nature provides rain and plants can send new roots searching for food, the nutrients available to a houseplant are limited by the amount of soil in the pot and whatever else you give it as a supplement. We recommend using approximately 2 tablespoons of McDonald Greenleaf fertilizer (organic or traditional formulas).

After repotting, your plant should be happy and healthy for the next one-to-two years, as long as you give it the light required and continue to feed and water according to its specific needs.

The McDonald Garden Center Southern Red Oak Tree

Towering a colossal 70-feet tall and 96-feet wide, this Southern Red Oak stands near the glass pavilion and alongside the deck at the McDonald Garden Center Independence location and has long been an iconic fixture at the garden center.

The Southern Red Oak began life in the mid to late 1800’s and was most likely planted to mark the property line at that time. In 2000, construction began on the Glass Pavilion. The raised deck was constructed to leave the tree roots undisturbed. Paving on the west side of the tree is the actual floor of the farm tractor shed built many years prior. The Music of the Spheres wind chimes were added in 2002, to enhance the graceful charm of this grand old tree. If you haven't already, be sure to stop and take a moment to enjoy the soothing sounds of the beautiful wind chime as it plays its song in a gentle breeze. Here are a few interesting facts about the McDonald Garden Center Southern Red Oak:

  • 155-inches in circumference or 49-inches in diameter (these measurements give the tree 321 Virginia Big Tree points in 2018).
  • For more about Virginia Champion trees go to http://bigtree.cnre.vt.edu/index.html
  • This tree cools the area as much as 5-9 degrees on hot summer days.
  • Over the life of the tree, it has sequestered over 20,000 pounds of carbon and release tons of oxygen back into the atmosphere.
  • For more information about the many benefits of trees go to www.greenhealth.washington.edu
Pampas Grass Ivory Feather
Lymus Blue Dune
Muhlenbergia
Pennisetum Hameln
Panicum Cheyenne Sky

Plume-tastic Ornamental Grasses

Ornamental grasses are treasured for their hardiness, ease of care, dramatic appearance, and the wide variety of colors, textures, and sizes available. And, today’s ornamental grasses are worlds apart from what was available a few years ago. There are more varieties to choose from, colorful foliage for season-long interest, and shorter, more compact selections for growing in containers and small spaces. Many varieties bloom all season, not just in fall like warm season perennial grasses. Their color palettes range from green to blue, copper, cream, red, and purple. Size varies by variety, so be sure to research them carefully when designing your combinations. Whether you use them as screens, accents, or focal points, ornamental grasses can play an intrigal part in your garden or landscape. Here are a few of our favorites:

Pampas Grass Ivory Feather - displays long stalks of dramatic, creamy white plumes above a dense cluster of green foliage that blooms from late summer until late fall. This perennial grass is wind and drought tolerant and provides a dazzling windbreak or screen. Foliage reaches 3 to 5 feet tall and 4 to 6 feet wide, reaching 8 to 10 feet tall with plumes. The flowers are beautiful when used in cut flower arrangements. Ivory Feather prefers full sun locations.

Lymus Blue Dune – a cool-season grass with striking, silver-blue and wheat-colored plumes in summer. Foliage clumps spread by rhizomes, making it ideal for filling in large areas quickly and for erosion control. This grass is heat tolerant and prefers a dry, sunny location. Blue Dune quickly forms clumps 2 feet tall and wide and reaches up to 3 feet tall when in bloom. Plant in partial to full sun.

Muhlenbergia (Muhly Grass) – is a showy, warm season grass with slender leaves and eye-catching reddish-mauve flower plumes that appear in late summer and fall. This grass’s fine-textured and soft green foliage forms a tidy mound and is ideal when planted in mass, as an accent mixed into perennial borders, or as a thriller in containers. Like most ornamental grasses, muhlenbergia is heat and drought tolerant and low maintenance. Plant in full to partial shade.

Pennisetum Hameln – the slim foliage and flowery plumes of this ornamental grass adds unique form to the fall garden. Foliage turns a lovely golden-russet color in autumn, creating bold contrast when used with shrubs or as a backdrop in perennial beds. This tough and waterwise grass is right at home in beds, borders, and on slopes. Hameln is a moderate grower, reaching 2 to 3 feet tall and 1 to 2 feet wide. Prefers full sun locations.

Panicum Cheyenne Sky - boasts dense, upright clumps of blue-green leaves that turn wine-red in early summer. Purple flower panicles appear atop foliage in late summer. Both drought and salt tolerant, this grass is also deer resistant and provides protection for songbirds in winter. This petite grass is ideal in containers and also provides erosion control. Cheyenne Sky reaches 3 to 4 feet tall by 2 feet wide and prefers partial to full sun.

How to Revitalize your Spring Annuals for Summer

Check out the video for tips on revitalizing spring annuals:

This time of year, you’re probably wondering if there’s any hope for those annuals that have gotten leggy and overgrown. Most of the annual baskets and containers you buy in early April have been growing since January, and will give you plenty of gorgeous color right through May into early summer. But with their big blooms and fast growth, they can use up available nutrients in the soil quickly. Here are some tips on what the Garden Guru, Mike Westphal, does to transition spring annual superstars into summer stunners.

Give Annual Hanging Baskets and Container Plants a Mid-Summer Trim - by sacrificing some blooms now, the pay-off will be fuller plants and more blooms later. So, grab your shears, take a deep breath, and cut back your annual hanging baskets and containers by half or back to the container.

Fertilize - fertilization is key, as plants need a lot of nutrients in order to sustain large growth and blooms. Every time you water, the nutrients that the plant has not already used are leeched out of the soil. By consistently feeding, you are ensuring that your plants maintain all the nutrition necessary to grow and bloom big. We use McDonald Greenleaf (available in organic or traditional formulas), which was developed specifically for plants in Hampton Roads and is a great general all-purpose, slow-release fertilizer. Simply sprinkle two tablespoons of Greenleaf around the basket or container.

Hydrate - water your baskets and containers as usual and in two to three weeks, they’ll be in full bloom once again.

Firepower Nandina
Abelia Kaleidoscope
Azaleas

Standout Shrubs with Mike Westphal, the Garden Guru.

Shrubs are some of the most important plants in the landscape offering color, texture, and oftentimes four-season interest. They can also create shade, attract birds or give you privacy from neighbors or a busy street. Mike Westpahl, McDonald Garden Center’s Garden Guru, has selected three of his favorite shrubs that thrive in Hampton Roads.
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Firepower Nandina – the perfect choice if you’re looking to add easy color and texture to the landscape. Firepower is one of the best coloring nandina with bright green foliage in spring that turns a brilliant fire-red in fall through winter. Firepower is loved for its oriental appeal with their bamboo-like stalks and fern-like foliage. This sun-loving, evergreen shrub reaches approximately 30 inches tall and wide and is ideal in borders, mass planting, or containers.

Kaleidoscope Abelia - provides continually swirling color throughout all seasons featuring variegated, bright yellow and green foliage and petite, white flowers during the warm season that changes to brilliant shades of red and deep orange during the winter months. This low, compact selection reaches 2 to 2 1/2 feet tall and 3 to 3 1/2 feet wide and works well as a foundation plant, low hedge, mass planting or in patio containers. Abelia prefers partial to full sun.

Encore Azaleas – if you love the colorful flowers that an azaleas offers, then you'll love the Encore varieties. Encores bloom three times per year - summer, spring, and fall, yes, even fall! This repeat bloomer adds vivid, multi-seasonal color unlike any other azalea and can grow to 2 feet tall and 2 feet wide or 5 feet by 5 feet, depending on the variety. Perfect planted in garden beds and borders, foundation plantings, large containers or as a focal point in the garden. Encore prefer partial sun to partial shade, although they can tolerate more sun than most other varieties.

At McDonald Garden Center, you'll find a wide variety of shrubs that flourish in our area. Our expert staff can help find the right varieties for any situation.