Johnston County Center: The Gardener's Dirt February 2009

RAISED BEDS

By Patty Brown
Johnston County Extension Master Gardener

Avid gardeners often spend the winter browsing through seed catalogs, considering changes to their landscapes, and otherwise planning for spring. If you have a problem spot in your yard, especially an area with poor drainage, you may want to consider adding a raised bed to your spring landscape plans.

By definition, a raised bed is an area higher than the surrounding soil level. The higher soil level promotes good drainage, which is essential for the health and optimum growth of almost all vegetables (and most other plants, too). Raised beds should be filled with loose, fast-draining soil that is rich in organic matter and deep enough (generally 8-12”) for plants to develop healthy root systems. Loose, well-drained soil isn’t waterlogged by heavy rains and so doesn’t suffocate plants’ roots. In addition, because air circulates more freely in looser soil, the soil in raised beds warms earlier in the spring, which can lengthen the growing season a bit. Raised beds can be cultivated to provide an increased yield (see Intensive Vegetable Gardening in the Sources section) and have the potential to be an attractive design element in the landscape. Because they don’t require quite so much bending as ground-level plantings, they can also be somewhat easier to maintain and easier on our backs!

Below are guidelines to keep in mind when planning for a raised bed and construction tips.

Location

Choose a sunny spot — For most vegetables and flowers, choose a location that gets at least 6 hours of sun daily.
Proximity to water and kitchen — Locate the bed near a source of water to provide irrigation. (Soil in a raised bed tends to dry out faster than that at ground level.) It’s helpful to place beds for vegetables and/or herbs near the kitchen, if possible, or at least in a visible and easily accessible spot. This helps ensure that plants aren’t overlooked and makes it easier to harvest at just the right time.

Construction

Size and shape — Raised beds can be any shape and size, although square or rectangular beds are often used for vegetables. A height of at least 8-12” deep is recommended. Consider keeping the width of the bed narrow enough so that you can reach across it for planting and weeding; a 4’ wide bed meets these specifications. For free-form beds, try outlining the shape with a garden hose, which can be easily adjusted until the desired result is achieved. Once the bed shape and location is determined, remove all weeds, grass and roots from the area.

Materials —To hold the soil in place, raised beds can be framed by materials such as wood, rocks, bricks or cinderblocks. Borderless beds can be formed by raking soil into mounds, then sloping and tamping down the sides of the bed to prevent soil erosion.

To create a simple 4’ x 8’ by 8” high bed with a wood border, you can purchase three 8’-long 2” x 8” boards. Cut one board in half so that you have two 4’-long lengths for the ends of the bed. Use the other two boards for the sides of the bed. Number 12 or 16 common galvanized nails (twisted or ring-shank for better grip) can be used to nail the boards together. To keep the nails from splitting the boards, drill starter holes into the wood before nailing.

Bed and soil preparation — If the garden soil is not deep, you can double dig the bed. To do this, remove the top 9-12” of the soil from a small section of the bed and set it aside. Insert a spade or spading fork into the soil and break up the compacted layers. Repeat for the remainder of the bed.

Mix the topsoil that was removed with organic material such as compost or manure. Additional soil can be purchased (or obtained from nearby areas) to fill the bed and should be amended as above. The finished soil mixture should be at least 1/3 organic material. Sand can be added to improve porosity.

Once the bed area is ready, rake the prepared soil into the center of the bed area. If you’re using a frame, install the frame around it. Spread the soil inside the frame until it is 1-2” from the top edge. If you’re not using a border, slope the edges of the bed and tamp them down.

Water the bed, let the soil settle for a few days, then plant.

About using wood to border your raised bed —

Experts recommend that creosote-treated railroad ties not be used as a border. Creosote from these ties can leach into the soil for several years and release vapors even longer. Young seedlings can be killed if planted within 6-10” of newly treated railroad ties.
Pressure-treated wood containing chromated copper arsenate (CCA) is now banned for most residential uses. For treating lumber used in the home and garden, the Environmental Protection Agency (EPA) has approved new chemical compounds that do not contain arsenic. When purchasing new lumber, check the tags stapled to the ends of the boards to determine the type of preservative being used and follow all recommendations for safe handling.
If you prefer to use untreated wood, rot resistant species such as redwood or cedar are suggested. Using synthetic lumber made from recycled plastic is another option.

Sources:
Gardening Note #11, Making Raised Beds, Cumberland County Master Gardeners
http://www.ces.ncsu.edu/cumberland/hotline/gardenincumb/gardennote11.html

Intensive Vegetable Gardening, NC State University College of Agriculture and Life Sciences, Cooperative Extension, Horticultural Science
http://www.ces.ncsu.edu/depts/hort/consumer/quickref/vegetable/intensive_veg_gardening.html

New generation of pressure-treated wood is safer for home use, Oregon State University Extension Service,
http://extension.oregonstate.edu/news/story.php?S_No=989&storyType=garde

Ortho’s Complete Guide to Successful Gardening, © 1983, Chevron Chemical Company.

The Complete Book of Practical Gardening, Peter McHoy with Susan Berry and Steve Bradley, © Arness Publishing Limited, 1997, 2001.

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Red Heleborus in flower

Helleborus orientalis

Tree Pruning Workshop Feb. 7, 10:00am, Johnston County Agriculture Center, 2736 NC highway 210, Smithfield. We will be pleased to have two representatives from the Forest Service here to teach us how to properly prune dormant shade trees. After a short class on the how-to's there will be some time to practice on some of the trees in the landscape at the Johnston County Agriculture Center. For more information contact Shawn Banks at 989-5380.

Grapevine Pruning Demonstration Feb. 21, 10:00am, Hinnant Family Vineyard, 826 Pine Level-Micro Rd, Pine Level. For more information on this class visit http://johnston.ces.ncsu.edu/content/Grapevine_Pruning or contact Shawn Banks at 989-5380..

Fruit Tree Pruning Demonstration March 7, 10:00 am, Central Crops Research Station, 13223 Us Business 70 West, Clayton. For more information on this class visit http://johnston.ces.ncsu.edu/content/FruitTree-Training or contact Shawn Banks at 989-5380.

2009 Tree and Shrub Sale. The Johnston County Master Gardeners are holding their annual Tree and Shrub sale. The list of plants and order form is available as a pdf by clicking this link . This year there are several plants that are newer plants to the landscape trade.

2nd Annual Film Feastival Feb. 7, 2:00 - 4:00pm, Meredith College Kresge Auditorium. This year the emphasis is on Community Gardens and local food. Learn more by visiting their web site at http://www.evite.com/app/publicUrl/QNZWFGMHYPBVNIBRLLIO/filmfeastival .

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Tetranychidae, PROSTIGMATA

Lawn Care

Cool season grasses should be fertilized mid-month. If a soil sample has not been taken, use a fertilizer of at least 30% slow release Nitrogen at the rate of 1 pound of nitrogen per 1000 square feet.
Crabgrass usually will start to germinate about the same time the Forsythia blooms. If you have had problems with crabgrass in the past, then you may want to apply crabgrass preventer when the Forsythia blooms.
Pulling wild onion/wild garlic is the best way to get rid of these pesky bulbs, but make sure you get the bulb. If there are too many to pull, a product with 2,4-D works well to help control this weed. Be sure to follow the manufactures directions found on the label. Complete control may take two or more years. Apply 2,4-D at half the recommended rate on centipede lawns otherwise it will damage the grass.
For more tips on lawn care visit Turf Files on the internet.

Trees, Shrubs, and Ornamentals

Cut back dormant ornamental grasses before new growth starts to about 10 to 14 inches above the soil. Evergreen ornamental grasses (or grass like ornamentals) such as Liriope and Mondo Grass should be cut short or mowed to remove last year’s unsightly foliage. If the clumps have become too big for the area they can be divided and shared with friends or planted in other areas of the yard.
Summer blooming shrubs bloom on new growth so they can be pruned hard in February to encourage new growth and many flowers. Examples include Abelia, Hibiscus, Hydrangea, Beautyberry, Butterfly bush, Althea, Rose of Sharon, and bush or Tea Roses. Shrub Pruning Calendar
Spring blooming shrubs such as Azaleas, Rhododendrons, Forsythia, Spirea, Quince, Weigela, and Climbing Roses bloom on last years growth and should not be pruned until after they have flowered.
Deciduous trees especially those that bloom in the spring should not be pruned this time of the year. Examples being Dogwoods, Red Buds, Maples and several others.
For many evergreens this is the best time of the year to prune if they haven't been pruned already. Evergreen Pruning Calendar
Summer blooming roses can be pruned this time of the year. Remember not to remove more than 1/3 of the growth. Remove old mulch and leaves from around plants, this removes many overwintering fungal spores. Put down fresh mulch.
Bare root roses and trees can be planted this time of the year. Soak the roots overnight to rehydrate them before planting.
Spring flowers such as Sweet Williams, Pansy, Viola, Calendula, Forget-Me-Nots, English Daisies, Poppy, Alyssum and Dianthus can be planted now. Don't forget to deadhead pansies and fertilize toward the end of the month.

Edibles

Asparagus crowns can be planted now through March.
Transplant cabbage, broccoli, and cauliflower out into the garden.
Strawberry plants can be planted now for spring fruits.
Beats, carrots, peas, lettuce, mustard, radish, spinach, irish potatoes, and turnips can be sown outside.
Starting seeds indoors is easy and economical. Sometimes it is the only way to get the color or variety of the plants you want to grow. It is not necessary to use "grow lights", ordinary florescent tubes will usually be enough. For more information you can read the pamphlet "Starting Plants from Seeds", it is on the web at http://www.ces.ncsu.edu/depts/hort/hil/hil-8703.html
February and March are good months to prune fruit trees.
It is time to start a spray program for peach trees to control the many diseases and insects that attack peaches.

Insects

Control overwintering insects such as scale and their eggs by hand picking or using a dormant oil spray (also know as horticultural oil ). Be sure to check for scales before spraying and follow the manufactures directions when applying any pesticide. Do not apply dormant oils to broadleaf evergreens when freezing temperatures are expected.
Cool-weather mites are not visible to the naked eye. Junipers and other needled evergreens are a favorite hang out these mites. If you had some of these plants that were an unsightly brown last year, check them with a hand held magnifying glass to see if cool season mites are to blame. Horticultural oil or other registered insecticides can improve their situation and appearance.

Houseplants

Even houseplants need a little rest once in a while, and this is a good time to give them a rest. Keep them watered but give them a break from the fertilizer as most houseplants don't do much growing during the short days of winter.
Turn and prune houseplants regularly to keep them shapely. Pinch back new growth to promote busy plants.
While this may sound extremely silly, your houseplants will thank you for it. When dusting the furniture, also dust the plants. Wipe dust from broad-leaf plants at regular intervals using a cloth dampened with clean water. If the plant has small leaves, consider placing several in the shower to wash the dust off.
Keep an eye open for pest on indoor plants. Most can be treated with insecticidal soaps.

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HELPING PEOPLE PUT KNOWLEDGE TO WORK.

Got Questions? We've got answers!

February 2009
The Gardener's Dirt Information you can dig into.		North Carolina State University College of Agriculture and Life Sciences North Carolina Cooperative Extension Service Johnston County Center 2736 NC 210 Highway * Smithfield, NC 27577 919 989-5380
Shawn Banks Extension Agent Agriculture—Consumer Horticulture
In this Issue Feature Article Spotlight Plant Announcements Pest Alert Gardening To-Do	This newsletter offers *timely information for your outdoor living spaces*. Addressing the most common questions ranging from container gardening, tree pruning, wildlife management, to fire ant control, insect identification and lawn establishment.
RAISED BEDS By Patty Brown Johnston County Extension Master Gardener Avid gardeners often spend the winter browsing through seed catalogs, considering changes to their landscapes, and otherwise planning for spring. If you have a problem spot in your yard, especially an area with poor drainage, you may want to consider adding a raised bed to your spring landscape plans. By definition, a raised bed is an area higher than the surrounding soil level. The higher soil level promotes good drainage, which is essential for the health and optimum growth of almost all vegetables (and most other plants, too). Raised beds should be filled with loose, fast-draining soil that is rich in organic matter and deep enough (generally 8-12”) for plants to develop healthy root systems. Loose, well-drained soil isn’t waterlogged by heavy rains and so doesn’t suffocate plants’ roots. In addition, because air circulates more freely in looser soil, the soil in raised beds warms earlier in the spring, which can lengthen the growing season a bit. Raised beds can be cultivated to provide an increased yield (see Intensive Vegetable Gardening in the Sources section) and have the potential to be an attractive design element in the landscape. Because they don’t require quite so much bending as ground-level plantings, they can also be somewhat easier to maintain and easier on our backs! Below are guidelines to keep in mind when planning for a raised bed and construction tips. Location Choose a sunny spot — For most vegetables and flowers, choose a location that gets at least 6 hours of sun daily. Proximity to water and kitchen — Locate the bed near a source of water to provide irrigation. (Soil in a raised bed tends to dry out faster than that at ground level.) It’s helpful to place beds for vegetables and/or herbs near the kitchen, if possible, or at least in a visible and easily accessible spot. This helps ensure that plants aren’t overlooked and makes it easier to harvest at just the right time. Construction Size and shape — Raised beds can be any shape and size, although square or rectangular beds are often used for vegetables. A height of at least 8-12” deep is recommended. Consider keeping the width of the bed narrow enough so that you can reach across it for planting and weeding; a 4’ wide bed meets these specifications. For free-form beds, try outlining the shape with a garden hose, which can be easily adjusted until the desired result is achieved. Once the bed shape and location is determined, remove all weeds, grass and roots from the area. Materials —To hold the soil in place, raised beds can be framed by materials such as wood, rocks, bricks or cinderblocks. Borderless beds can be formed by raking soil into mounds, then sloping and tamping down the sides of the bed to prevent soil erosion. To create a simple 4’ x 8’ by 8” high bed with a wood border, you can purchase three 8’-long 2” x 8” boards. Cut one board in half so that you have two 4’-long lengths for the ends of the bed. Use the other two boards for the sides of the bed. Number 12 or 16 common galvanized nails (twisted or ring-shank for better grip) can be used to nail the boards together. To keep the nails from splitting the boards, drill starter holes into the wood before nailing. Bed and soil preparation — If the garden soil is not deep, you can double dig the bed. To do this, remove the top 9-12” of the soil from a small section of the bed and set it aside. Insert a spade or spading fork into the soil and break up the compacted layers. Repeat for the remainder of the bed. Mix the topsoil that was removed with organic material such as compost or manure. Additional soil can be purchased (or obtained from nearby areas) to fill the bed and should be amended as above. The finished soil mixture should be at least 1/3 organic material. Sand can be added to improve porosity. Once the bed area is ready, rake the prepared soil into the center of the bed area. If you’re using a frame, install the frame around it. Spread the soil inside the frame until it is 1-2” from the top edge. If you’re not using a border, slope the edges of the bed and tamp them down. Water the bed, let the soil settle for a few days, then plant. About using wood to border your raised bed — Experts recommend that creosote-treated railroad ties not be used as a border. Creosote from these ties can leach into the soil for several years and release vapors even longer. Young seedlings can be killed if planted within 6-10” of newly treated railroad ties. Pressure-treated wood containing chromated copper arsenate (CCA) is now banned for most residential uses. For treating lumber used in the home and garden, the Environmental Protection Agency (EPA) has approved new chemical compounds that do not contain arsenic. When purchasing new lumber, check the tags stapled to the ends of the boards to determine the type of preservative being used and follow all recommendations for safe handling. If you prefer to use untreated wood, rot resistant species such as redwood or cedar are suggested. Using synthetic lumber made from recycled plastic is another option. Sources: Gardening Note #11, Making Raised Beds, Cumberland County Master Gardeners http://www.ces.ncsu.edu/cumberland/hotline/gardenincumb/gardennote11.html Intensive Vegetable Gardening, NC State University College of Agriculture and Life Sciences, Cooperative Extension, Horticultural Science http://www.ces.ncsu.edu/depts/hort/consumer/quickref/vegetable/intensive_veg_gardening.html New generation of pressure-treated wood is safer for home use, Oregon State University Extension Service, http://extension.oregonstate.edu/news/story.php?S_No=989&storyType=garde Ortho’s Complete Guide to Successful Gardening, © 1983, Chevron Chemical Company. The Complete Book of Practical Gardening, Peter McHoy with Susan Berry and Steve Bradley, © Arness Publishing Limited, 1997, 2001. Return to the top

Red Heleborus in flower	Helleborus orientalis Lenten Rose We were introduced to the Lenten Rose at a snowy birthday celebration one icy January. The table flowers were Lenten Roses from the host’s yard. Very beautiful! Helleborus orientalis, known as Christmas or Lenten Rose, originated in the Alps. The Lenten Rose is not related to the Rose family, but the Buttercup family. This low growing perennial will reach heights of 18 to 24 inches tall and wide, is very hardy, thriving in the shade or partial shade. Plants prefer a moist, rich organic, well-drained soil. One advantage is, they are deer resistant. The leathery leaves are deep green and often hide the buds. Lovely flowers in endless colors and color combinations of pure white to deep plum are available. Some varieties have combinations of colors on the same plant. They bloom in the winter, and blooming in the snow was quite spectacular! Lenten Rose is certain to be a wonderful addition to the garden. It is very easy to grow and the foliage makes an excellent ground cover. The entire plant is poisonous if eaten, so caution is in order with children, pets and adults.			Heleborus in the garden. Picture by Michelle Wallace.
Return to the top Tree Pruning Workshop Feb. 7, 10:00am, Johnston County Agriculture Center, 2736 NC highway 210, Smithfield. We will be pleased to have two representatives from the Forest Service here to teach us how to properly prune dormant shade trees. After a short class on the how-to's there will be some time to practice on some of the trees in the landscape at the Johnston County Agriculture Center. For more information contact Shawn Banks at 989-5380. Grapevine Pruning Demonstration Feb. 21, 10:00am, Hinnant Family Vineyard, 826 Pine Level-Micro Rd, Pine Level. For more information on this class visit http://johnston.ces.ncsu.edu/content/Grapevine_Pruning or contact Shawn Banks at 989-5380.. Fruit Tree Pruning Demonstration March 7, 10:00 am, Central Crops Research Station, 13223 Us Business 70 West, Clayton. For more information on this class visit http://johnston.ces.ncsu.edu/content/FruitTree-Training or contact Shawn Banks at 989-5380. 2009 Tree and Shrub Sale. The Johnston County Master Gardeners are holding their annual Tree and Shrub sale. The list of plants and order form is available as a pdf by clicking this link . This year there are several plants that are newer plants to the landscape trade. 2nd Annual Film Feastival Feb. 7, 2:00 - 4:00pm, Meredith College Kresge Auditorium. This year the emphasis is on Community Gardens and local food. Learn more by visiting their web site at http://www.evite.com/app/publicUrl/QNZWFGMHYPBVNIBRLLIO/filmfeastival . Return to the top
			Southern Red Mite Tetranychidae, PROSTIGMATA
Southern red mite is a dark red, cool weather mite. They are more closely related to spiders than insects. With their eight legs spread out they would just cover the period at the end of this sentence. Southern red mites are found in the eastern United States and California and prefer azaleas, hollies and camellias but they have been recorded from a number of shrubs and herbs. Southern red mites feed on the lower leaf surface, causing the mesophyll (the soft tissue inside a leaf, between the lower epidermis and the upper) to collapse. Infested leaves turn gray or brown and may fall prematurely. Heavily infested shrubs may die. Southern red mites over winter as eggs glued to the lower leaf surface. If the winter is mild, all stages of this mite may survive. As the weather moderates in late winter, southern red mite numbers increase. Most of the feeding damage occurs in early spring. When populations of predaceous insects and mites are active in summer, southern red mites dwindle away so that only the eggs survive in hot weather. If the summer is mild, all stages of this mite may survive. As temperatures cool in autumn, mite populations build up again. Return to the top
Lawn Care Cool season grasses should be fertilized mid-month. If a soil sample has not been taken, use a fertilizer of at least 30% slow release Nitrogen at the rate of 1 pound of nitrogen per 1000 square feet. Crabgrass usually will start to germinate about the same time the Forsythia blooms. If you have had problems with crabgrass in the past, then you may want to apply crabgrass preventer when the Forsythia blooms. Pulling wild onion/wild garlic is the best way to get rid of these pesky bulbs, but make sure you get the bulb. If there are too many to pull, a product with 2,4-D works well to help control this weed. Be sure to follow the manufactures directions found on the label. Complete control may take two or more years. Apply 2,4-D at half the recommended rate on centipede lawns otherwise it will damage the grass. For more tips on lawn care visit Turf Files on the internet. Trees, Shrubs, and Ornamentals Cut back dormant ornamental grasses before new growth starts to about 10 to 14 inches above the soil. Evergreen ornamental grasses (or grass like ornamentals) such as Liriope and Mondo Grass should be cut short or mowed to remove last year’s unsightly foliage. If the clumps have become too big for the area they can be divided and shared with friends or planted in other areas of the yard. Summer blooming shrubs bloom on new growth so they can be pruned hard in February to encourage new growth and many flowers. Examples include Abelia, Hibiscus, Hydrangea, Beautyberry, Butterfly bush, Althea, Rose of Sharon, and bush or Tea Roses. Shrub Pruning Calendar Spring blooming shrubs such as Azaleas, Rhododendrons, Forsythia, Spirea, Quince, Weigela, and Climbing Roses bloom on last years growth and should not be pruned until after they have flowered. Deciduous trees especially those that bloom in the spring should not be pruned this time of the year. Examples being Dogwoods, Red Buds, Maples and several others. For many evergreens this is the best time of the year to prune if they haven't been pruned already. Evergreen Pruning Calendar Summer blooming roses can be pruned this time of the year. Remember not to remove more than 1/3 of the growth. Remove old mulch and leaves from around plants, this removes many overwintering fungal spores. Put down fresh mulch. Bare root roses and trees can be planted this time of the year. Soak the roots overnight to rehydrate them before planting. Spring flowers such as Sweet Williams, Pansy, Viola, Calendula, Forget-Me-Nots, English Daisies, Poppy, Alyssum and Dianthus can be planted now. Don't forget to deadhead pansies and fertilize toward the end of the month. Edibles Asparagus crowns can be planted now through March. Transplant cabbage, broccoli, and cauliflower out into the garden. Strawberry plants can be planted now for spring fruits. Beats, carrots, peas, lettuce, mustard, radish, spinach, irish potatoes, and turnips can be sown outside. Starting seeds indoors is easy and economical. Sometimes it is the only way to get the color or variety of the plants you want to grow. It is not necessary to use "grow lights", ordinary florescent tubes will usually be enough. For more information you can read the pamphlet "Starting Plants from Seeds", it is on the web at http://www.ces.ncsu.edu/depts/hort/hil/hil-8703.html February and March are good months to prune fruit trees. It is time to start a spray program for peach trees to control the many diseases and insects that attack peaches. Insects Control overwintering insects such as scale and their eggs by hand picking or using a dormant oil spray (also know as horticultural oil ). Be sure to check for scales before spraying and follow the manufactures directions when applying any pesticide. Do not apply dormant oils to broadleaf evergreens when freezing temperatures are expected. Cool-weather mites are not visible to the naked eye. Junipers and other needled evergreens are a favorite hang out these mites. If you had some of these plants that were an unsightly brown last year, check them with a hand held magnifying glass to see if cool season mites are to blame. Horticultural oil or other registered insecticides can improve their situation and appearance. Houseplants Even houseplants need a little rest once in a while, and this is a good time to give them a rest. Keep them watered but give them a break from the fertilizer as most houseplants don't do much growing during the short days of winter. Turn and prune houseplants regularly to keep them shapely. Pinch back new growth to promote busy plants. While this may sound extremely silly, your houseplants will thank you for it. When dusting the furniture, also dust the plants. Wipe dust from broad-leaf plants at regular intervals using a cloth dampened with clean water. If the plant has small leaves, consider placing several in the shower to wash the dust off. Keep an eye open for pest on indoor plants. Most can be treated with insecticidal soaps. Return to the top
Need Help
HELPING PEOPLE PUT KNOWLEDGE TO WORK. Got Questions? We've got answers! If you have a gardening issue you would like to see addressed in this newsletter please let me know I will do what I can to get you the information you need. Contact me by e-mail at shawn_banks@ncsu.edu or by phone at (919) 989-5380. The Johnston County Master Gardener Volunteers are available Monday, Wednesday, or Friday from 1 to 4 pm to answer questions as well. They can also be contacted by phone at (919) 989-5380 or by e-mail at jcemastergardener@gmail.com.
Past Newsletters		Johnston County Lawn and Garden

February 2009

The Gardener's

Dirt

RAISED BEDS

Helleborus orientalis

Lenten Rose

Southern Red Mite

Need Help

HELPING PEOPLE PUT KNOWLEDGE TO WORK.