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Environmental Horticulture

Title Summary Date ID Author(s)
Annuals: Culture and Maintenance

Annual flowers live only for one growing season, during which they grow, flower, and produce seed, thereby completing their life cycle. Annuals must be set out or seeded every year since they don’t persist. Some varieties will self-sow, or naturally reseed themselves. This may be undesirable in many flowers because the parents of this seed are unknown and hybrid characteristics will be lost. Plants will scatter everywhere instead of growing in their designated spot. Examples are alyssum, petunias, and impatiens. Some perennials, which are plants that live from year to year, are classed with annuals because they are not winter-hardy and must be set out every year; begonias and snapdragons are examples. Annuals have many positive features. They are versatile, sturdy, and relatively cheap. Plant breeders have produced many new and improved varieties. Annuals are easy to grow, produce instant color, and, most important, they bloom for most of the growing season. Many annuals are able to thrive without the need of grooming due to their “self-cleaning” ability.

Jan 14, 2015 426-200 (HORT-85P)
Asparagus

 Asparagus is a perennial vegetable that will live from 12 to 15 years or longer. It is one of the most valuable of the early vegetables and is well adapted to freezer storage. During the harvest period (traditionally spring, but see below for summer harvest instructions), the spears develop daily from underground crowns. Asparagus does well where winters are cool and the soil occasionally freezes at least a few inches deep; it is considered very hardy.

Mar 6, 2015 426-401(HORT-152P)
Beans

Environmental Preferences

Light: sunny

Soil: well-drained

Fertility: medium rich

pH: 5.8 - 7.0

Temperature: warm (65 degrees - 80 degrees) except fava beans

Moisture: average

Apr 16, 2015 426-402 (HORT-145P)
Building Healthy Soil
Caring for the garden soil should be as important to home gardeners as it is to farmers. Improving the soil structure is one of the most important aspects of soil care, and adding organic matter is the most effective way to accomplish this. Organic matter also helps maintain the pH balance of the soil and adds nutrients.
Apr 21, 2015 426-711 (HORT-149P)
Calibrating Your Lawn Spreader

There are two basic types of fertilizer spreaders for use on the home lawn: the drop and the broadcast.

The drop type spreader (shown at left) "drops" a set rate of fertilizer. This type is best suited for a limited space in order to avoid wide dispersal on sidewalks and driveways. The amount of fertilizer that is spread depends on the opening setting, the type of fertilizer used, and the speed at which the spreader is pushed.

May 1, 2009 430-017
Care of Specialty Potted Plants

Improper water and light,and excessive heat are the leading causes of failure in caring for gift plants. These plants are grown in greenhouses, where the nighttime temperatures are cool, light is adequate, and the air is moist. When they are brought into a dry home, where the light is poor and the temperatures are maintained for human comfort, results are frequently disappointing. Do not expect to keep a gift plant from year to year. Enjoy them while they are attractive and in season, and then discard.

May 1, 2009 426-101
Cole Crops or Brassicas

All of the following crops are members of the cabbage family. It is best not to plant cabbage family crops in the same spot year after year, since diseases and insect pests will build up. Rotate crops within your garden. 

Apr 21, 2015 426-403 (HORT-156P)
Cucumbers, Melons and Squash

Varieties include both the slicer or fresh salad type and the pickle type (which can also be used fresh); vined, dwarfvined and bush varieties; all female or all-female seedless (no pollination required); burpless; and, various mixtures of these characteristics. Disease resistance is available in many varieties.

Mar 16, 2015 426-406 (HORT-147P)
Environmental Horticulture: Guide to Nutrient Management

Plants need 17 elements for normal growth. Carbon, hydrogen, and oxygen are found in air and water. Nitrogen, potassium, magnesium, calcium, phosphorous, and sulfur are found in the soil. These six elements are used in relatively large amounts by the plant and are called macronutrients. There are eight other elements that are used in much smaller amounts and are called micronutrients, or trace elements. The micronutrients, which are found in the soil, are iron, zinc, molybdenum, manganese, boron, copper, cobalt, and chlorine. All 17 elements, both macronutrients and micronutrients, are essential for plant growth.

May 1, 2009 426-613
Establishing Lawns

Producing quality lawns in Virginia can be challenging. Geographically, Virginia is located in what is known as the transition zone for turfgrasses. This means the climate can be hostile to both cool-season grasses (Kentucky bluegrass, tall fescue) and warm-season grasses (bermudagrass, zoysiagrass). However, with proper cultural practices, a healthy lawn can be established and maintained.

Turf may be established from seed, sprigs, plugs, or sod. The method depends on the grass species desired, the environmental conditions, time constraints, and financial considerations. If possible, use only certified seed and sod. The same requirements for soil preparation apply for all methods.

May 1, 2009 426-718
Fall Vegetable Gardening

By planning and planting a fall vegetable garden it is possible to have fresh vegetables up to and even past the first frosts. At the time of year when retail vegetable prices are on the rise, you can be reaping large and varied harvests from your still- productive garden site.

Many varieties of vegetables can be planted in mid- to late sum- mer for fall harvests. Succession plantings of warm season crops (such as corn and beans) can be harvested up until the first killing frost. Cool season crops (such as kale, turnips, mustard, broccoli, cabbage) grow well during the cool fall days and can withstand light frosts. Timely planting is the key to a successful fall garden.

May 1, 2009 426-334
Fertilizing the Vegetable Garden

The amount of fertilizer to apply to a garden depends on the natural fertility of the soil, the amount of organic matter present, the type of fertilizer used, and the crop being grown. The best way to determine fertilizer needs is to have the soil tested. Soil testing is available through your local Extension agent, through private labs, and with soil test kits which can be purchased from garden shops and catalogs.

Apr 16, 2015 426-323 (HORT-144P)
Flowering Bulbs: Culture and Maintenance

“Bulbs” is a term loosely used to include corms, tubers, tuberous roots, and rhizomes as well as true bulbs. This publication will refer to all of the above as bulbs. Many vegetables are propagated from or produce edible organs of these types (e.g., tuber, Irish potato; tuberous root, sweet potato; rhizome, Jerusalem artichoke; bulb, onion).

Jan 21, 2015 426-201(HORT-88P)
Growing Azaleas and Rhododendrons Mar 30, 2015 426-602 (HORT-103P)
Herb Culture and Use

Herbs have been used for seasoning, medicine, fragrance, and sorcery for thousands of years. Tarragon, rosemary, and thyme are among the most ancient of seasonings, yet there are few culinary achievements that can top good poultry roasted with these three herbs.

Nov 11, 2011 426-420
Home Hydroponics

Hydroponics is often defined as "the cultivation of plants in water." Research has since determined that many different aggregates or media will support plant growth; therefore, the definition of hydroponics has been broadened to read "the cultivation of plants without soil."

May 1, 2009 426-084
Home Landscape Practices to Protect Water Quality

In Virginia, we rely on reservoir systems, wells, and other sources for our freshwater. In recent years, our previously plentiful clean water supplies have been threatened not only by overuse, but also by contamination. Pollutants are carried down with water soaking through the soil to the water table. Runoff (water that does not soak into the ground) flows over the surface, often taking soil and polluting chemicals with it into lakes and streams.

Mar 19, 2015 426-723(HORT-137P)
Integrated Pest Management for Vegetable Gardens

Maintain a slightly acid soil (around pH 6.5). If in doubt, have a soil analysis done through your local Extension office, by a private lab, or with a commercial soil test kit. Lime can be used to increase soil pH and sulfur can lower it.

Maintain adequate levels of soil fertility through additions of potassium and phosphorus releasing materials, such as commercial fertilizers or animal manures. Soil testing should be done every three years to determine levels of these important nutrients.

Build a biologically active, healthy soil through regular addition of organic matter, such as yard waste, compost, and manure.

For planting areas not being cropped, grow annual cover crops, such as clover or rye grass, to provide additional organic matter.

Till the soil in the fall to expose pests living near the surface to natural enemies and weather, and to destroy insects overwintering in crop residues.

May 1, 2009 426-708
Landscaping for Less in the Landfill

Virginia is rapidly running out of landfill space. Fifteen to twenty percent of solid waste sent to landfills is comprised of leaves, grass clippings, and other yard wastes. Gardeners can plan their landscapes to produce less yard waste and use what is produced around their homes to enhance yards, gardens, and soil.

Apr 22, 2015 426-716 (HORT-162P)
Leafy Green Vegetables

Lettuce, a cool-season vegetable crop, is one of the easiest to grow. Lettuce withstands light frost; however, sunlight and high summer temperatures usually cause seedstalk formation (bolting) and bitter flavor. Slow-bolting or heat-resistant varieties are available and are recommended for extending the lettuce-growing season.

Mar 16, 2015 426-408 (HORT-148P)
Making Compost from Yard Waste

Compost is one of the most valuable resources for beautifying your landscape, and it is virtually free. The leaves you rake, the grass you mow, and the branches you trim are some of the ingredients you can use to make compost. Finished compost is dark and has a pleasant smell. It is produced when organic matter — such as garden, lawn, and kitchen waste — is broken down by bacteria and fungi. 

Use compost throughout your landscape: dig it into gardens and flower beds, add it to the soil when renovating your lawn, or put it through a sieve and use it in potting soil.

Oct 18, 2012 426-703 (HORT-46P)
Managing Winter Injury to Trees and Shrubs

It is often necessary to provide extra attention to plants in the fall to help them over-winter and start spring in peak condition. Understanding certain principles and cultural practices will significantly reduce winter damage that can be divided into three categories: desiccation, freezing, and breakage.

Apr 9, 2015 426-500 (HORT-121P)
Minimum Chemical Gardening

Home gardeners often use more pesticides per square foot in their gardens than farmers do in the fields, thinking that if a little is good, more will be better. This is a serious mistake, and a misuse of pesticides. Over-use of pesticides has a number of adverse effects: it makes your food less safe to eat, especially if there are residues at harvest time; it makes handling the plants more dangerous; beneficial insects, earthworms, birds, even pets may be harmed or killed along with the "bad guys;" each time the gardener sprays, she or he is exposed to the dangers of inhalation or absorption of the toxin; pesticides used near water may contaminate the water supply; continuous use of certain pesticides may induce resistance in the pests, thus requiring the gardener to switch to more toxic substances; some pesticides do not break down easily and can remain in the environment for years.

Apr 22, 2015 426-366 (HORT-161P)
Mulches for the Home Vegetable Garden

Mulching is a practice adaptable to nearly all home gardens. To mulch is simply to cover the soil around plants with a protective material, organic or inorganic.

Mar 20, 2015 426-326(HORT-140P)
Mulching for a Healthy Landscape

Soil erosion occurs when soil particles are carried off by water or wind and deposited somewhere else such as into a stream or at the bottom of a bay. Often soil particles are carried by runoff, water that does not soak into the ground, but flows over the surface and runs to another area – such as into stormdrains, streams, or lakes.

May 22, 2015 426-724(HORT-127P)
Onions, Garlic, and Shallots

Onions are often grouped according to taste. The two main types of onions are strong flavored (American) and mild (often called European). Each has three distinct colors, yellow, white, and red. In general, the American onion produces bulbs of smaller size, denser texture, stronger flavor, and better keeping quality than European types. Globe varieties tend to keep longer in storage.

Mar 16, 2015 426-411(HORT-143P)
Perennials: Culture, Maintenance and Propagation

Perennials are plants that live year after year. Trees and shrubs are perennial. Most garden flowers are herbaceous perennials. This means the tops of the plants (the leaves, stems, and flowers) die back to the ground each fall with the first frost or freeze. The roots persist through the winter, and every spring new plant tops arise. Any plant that lives through the winter is said to be hard

May 1, 2009 426-203
Pest Management for Water Quality

Research has shown that consumers find reading and understanding the label to be the most difficult aspect of applying pesticides. However, an understanding of the label information is essential before work begins. The label printed on or attached to a container of pesticide tells how to use it correctly and warns of any environmental or health safety measures to take. Read the label when you purchase a pesticide and again before mixing or applying it. If you are confused about any part of the label, consult your Extension agent or a representative of the company that makes the product. Many pesticides now list a toll-free number for consumers. The label includes specific information that you should be aware of and learn to understand.

Mar 18, 2015 426-615 (HORT-138P)
Planning the Flower Border

Much of the excitement of creating an herbaceous border lies in its great flexibility of design. In form, placement, and selection of plants, the contemporary border follows few rigid rules and allows fullest expression of the gardener’s taste.

Jan 14, 2015 426-202 (HORT-87P)
Plant Propagation from Seed

Sexual propagation involves the union of the pollen (male) with the egg (female) to produce a seed. The seed is made up of three main parts: the outer seed coat, which protects the seed; a food reserve (e.g., the endosperm); and the embryo, which is the young plant itself. When a seed is mature and put in a favorable environment, it will germinate, or begin active growth. In the following section, seed germination and transplanting of seeds will be discussed.

May 1, 2009 426-001
Planting Trees

Aesthetics. Trees are creatures of beauty and grandeur. They offer beauty in each season with their form, bark, foliage, flowers, fruit, and sometimes fragrance.

In addition to their seasonal variations, they change in size and character over time. Some trees will become quite large and are magnificent just for their size, irrespective of their species.
May 1, 2009 426-702
Planting on Your Septic Drain Field

Perhaps the most entertaining answer to the question 'What should I plant over a septic system's leach field?' is 'Something fragrant.' Although the question arises often, there are few hard and fast answers as to what can be planted, because every drain field is unique. You can decide what will work best in each situation, however, by following a few simple guidelines.

Oct 15, 2010 426-617
Potatoes, Peppers and Eggplant

Environmental Preferences

LIGHT: Sunny.

SOIL: Well-drained with moderate organic matter.

FERTILITY: Medium-rich.

pH: 4.8 to 6.5

TEMPERATURE: Cool (55 TO 65°F).

MOISTURE: Uniform moisture, especially while tubers are developing.

Apr 16, 2015 426-413 (HORT-146P)
Propagation by Cuttings, Layering and Division

Asexual propagation is the best way to maintain some species, particularly an individual that best represents that species. Clones are groups of plants that are identical to their one parent and that can only be propagated asexually. The Bartlett pear (1770) and the Delicious apple (1870) are two examples of clones that have been asexually propagated for many years.

The major methods of asexual propagation are cuttings, layering, division, and budding/grafting. Cuttings involve rooting a severed piece of the parent plant; layering involves rooting a part of the parent and then severing it; and budding and grafting are joining two plant parts from different varieties.

May 1, 2009 426-002
Reducing Erosion and Runoff

Soil erosion occurs when soil particles are carried off by water or wind and deposited somewhere else such as into a stream or at the bottom of a bay. Often soil particles are carried by runoff, water that does not soak into the ground, but flows over the surface and runs to another area – such as into stormdrains, streams, or lakes.

May 22, 2015 426-722(HORT-116P)
Root Crops Mar 5, 2015 426-422 (HORT-150P)
Season Extenders

To get the most out of a garden, you can extend the growing season by sheltering plants from cold weather both in early spring and during the fall. Very ambitious gardeners harvest greens and other cool-weather crops all winter by providing the right conditions. There are many ways to lengthen the growing season, and your choice depends on the amount of time and money you want to invest.

Apr 22, 2015 426-381 (HORT-159P)
Seed For The Garden

Choosing and purchasing vegetable seeds is one of the most enjoyable gardening pastimes. Thumbing through colorful catalogs and dreaming of the season¼s harvest is one way to make winter seem a little warmer. Seed purchased from a dependable seed company will provide a good start toward realizing that vision of bounty. Keep notes about the seeds you purchase - their germination qualities, vigor of plants, tendencies toward insects and disease, etc. From this information, you can determine whether one seed company is not meeting your needs, or whether the varieties you have chosen are unsuitable for your area or gardening style. For example, if powdery mildew is a big problem on squash family plants in your area, the next year, you may want to look for mildew-resistant varieties.

Apr 21, 2015 426-316 (HORT-153P)
Selecting Landscape Plants: Broad-Leaved Evergreens Apr 3, 2015 426-607 (HORT-105P)
Selecting Landscape Plants: Conifers Apr 6, 2015 426-605 (HORT-108P)
Selecting Landscape Plants: Flowering Trees

In the home landscape, flowering trees are secondary in importance to shade trees. The basic elements of framing, background, and shading are provided by shade trees, while flowering trees provide showy and unusual features with their floral beauty and seasonal interest. In addition, many flowering trees have colorful or interesting fruits which may be edible or attractive to birds.

May 1, 2009 426-611
Selecting Landscape Plants: Groundcovers

Ground covers are low-growing plants that spread quickly to form a dense cover. They add beauty to the landscape and, at the same time, help prevent soil erosion. Grass is the best known ground cover, but grass is not suited to all locations. Other ground cover plants should be used where grass is difficult to grow or maintain.

Nov 29, 2012 426-609 (HORT-31P)
Selecting Landscape Plants: Rare and Unusual Trees

There are many tree species that can be successfully grown in Virginia, but are rarely seen in our landscapes. Although not ordinarily recommended or readily available, these trees may be useful to carry out a specific landscape theme, to substitute for an exotic type which is not locally adapted, or may be prized for unusual form, flowers, fruits, bark, or foliage.

May 1, 2009 426-604
Selecting Landscape Plants: Shade Trees Apr 1, 2015 426-610 (HORT-104P)
Selecting Turfgrass

A quality lawn results from using the right grass species and/or variety, proper planting and establishment, and sound management. Planting the right turfgrass for your site reduces the need for pesticides. The most important step for the homeowner is selecting the proper turfgrass for the situation.

May 1, 2009 426-719
Small Fruit in the Home Garden

The small fruits offer advantages over fruit trees for home culture. They require a minimum of space for the amount of fruit produced and bear one or two years after planting. Also, pest control typically is easier than with most tree fruits.

Success with a small fruit planting will depend on the attention given to all phases of production: variety selection, soil management, fertilization, pruning, and pest control. Plant only what you can care for properly. It is better to have a well-attended, small planting than a neglected, large one.

May 1, 2009 426-840
Sprouting Seeds For Food
Seeds themselves are a very nutritious form of food because they contain proteins, carbohydrates, vitamins, minerals, and oils that a beginning plant needs to grow. Many of these constituents are increased greatly when the seeds are sprouted.

If their presence in restaurant salad bars and in grocery stores is any indication, the popularity of sprouts is increasing. It's very easy to grow your own sprouts at home with a minimum of supplies.

Mar 6, 2015 426-419 (HORT-154P)
Storing Pesticides Safely
Storage Tips
The proper storage of pesticides, both synthetic and botanical, in and around the home is important for many reasons, including protecting human health, preserving the environment, and maintaining chemical effectiveness. One way to minimize storage problems is through good planning.

Buy only the amount of pesticide that you need for a specific job or for the current growing season. The smaller-volume containers, even if more expensive ounce for ounce, may in fact be the "best buy" in the long run by eliminating waste and the need for storage space. If you need to store pesticides on your property, follow these guidelines - for safety's sake!

May 1, 2009 426-705
Sweet Corn

Sweet corn varieties differ significantly in time to maturity and in quality; yellow, white, bi-color, standard, and extra-sweet varieties are available. Most varieties planted are hybrids which have been bred for greater vigor and higher yields. A continuous harvest can be planned by planting early, mid-season, and late-season varieties or by making successive plantings of the same variety every two weeks or when the last planting has three to four leaves (corn sown in early spring will take longer because of cool temperatures).

Mar 16, 2015 426-405 (HORT-151P)
The Art of Bonsai

Bonsai is an art form that stems from ancient Asian culture, originating in China and developed by the Japanese. In the 13th century, the Japanese collected and potted wild trees that had been dwarfed by nature. These naturally formed miniatures were some of the first bonsai.

Mar 3, 2015 426-601 (HORT-158P)
The Value of Landscaping Apr 6, 2015 426-721 (HORT-109P)
Tomatoes

Tomatoes are valuable garden plants in that they require relatively little space for large production. Each standard tomato plant, properly cared for, yields 10 to 15 pounds or more of fruit.

Mar 17, 2015 426-418 (HORT-142P)
Using Compost in Your Landscape

Compost is produced when organic matter, such as garden and lawn waste, is broken down by bacteria and fungi.

When added to soil it improves soil structure; sandy soils will hold water better while clays will drain faster. Compost also promotes a biologically healthy soil by providing food for earthworms, soil insects, and beneficial microorganisms.

May 1, 2009 426-704
Vegetable Gardening in Containers

If you don’t have space for a vegetable garden or if your present site is too small, consider raising fresh, nutritious, homegrown vegetables in containers. A window sill, patio, balcony, or doorstep can provide sufficient space for a productive container garden. Problems with soil-borne diseases, nematodes, or poor soil can also be overcome by switching to container gardening.

Mar 18, 2015 426-336 (HORT-141P)
Vegetables Recommended for Virginia

Table of vegetable recommendations for Virginia.

May 1, 2009 426-480
Weeds in the Home Vegetable Garden

The most common definition of a weed is a plant out of place. Many plants that are considered weeds in the vegetable garden are beneficial wildflowers in other settings. Some, such as the Venice mallow (or flower-of-an-hour), morning glory, and even thistles, have flowers that rival those intentionally planted in flower beds. Unfortunately, some of the plants, while attractive in the wild, are too aggressive for use in the home garden and can take over the landscape. Seeds of even very obnoxious wild flowers may be sold occasionally, so care must be used in the selection of wildflowers vs. weeds.

Apr 22, 2015 426-364 (HORT-157P)