Annuals are essential to any summer garden where color is important. The term annual refers simply to any plant that completes its life cycle in one season, but in the gardening world, it also is used to refer to plants that are grown for just one season. Most often, annuals are valued for the color they bring to the garden. That color can be provided either by blooms or foliage. This information sheet will provide basic information about many of the annuals that are commonly used in our region. For information on other annuals that are also nice additions to our summer gardens, check out the information sheet entitled Underused Annuals. And for more details regarding impatiens, geraniums, begonias, coleus, petunias and zinnias, there are full information sheets on each of those plants. All of the annuals listed below can be started from seed but unless you have lots of room and lights to get them going early, it is better to buy them at any of the seven Bachman’s garden centers. These plants are ready to go as soon as the weather is warm enough to plant them out.
Ageratum is also sometimes called floss flower. Most varieties of ageratum are short, compact plants that bear dense heads of fuzzy blue, rose or white flowers. There are also a few varieties that grow much taller and are excellent cut flowers. Ageratum grows best in full sun and well-drained soil. They will tolerate light shade. To encourage better blooming, deadhead ageratum when the flowers pass their prime. Ageratum will not tolerate cool air and soil temperatures so
wait until later in May to plant them outside.
Alyssum Popularly known as sweet alyssum, is a great low-growing annual for borders and containers. It forms clusters of tiny, sweetly fragranced flowers on plants with very fine foliage. Sweet alyssum is most commonly available in white, purple and rose. Watch for the new peach-colored variety too. Alyssum does its best during the cool parts of the season. Plant it where it will get lots of strong light but be shaded from the heat of the afternoon. It prefers well-drained soil and requires frequent fertilization to keep it blooming. If the plant gets floppy shear it back and will grow back with ore bloom.
Begonia The type of begonia most often used as a bedding plant is the fibrous or wax-leaf begonia. It is valued as a low-maintenance, heat-tolerant plant that provides color both from its flowers and its foliage. Depending on the variety, leaves are either bronze or green and always very glossy. Flowers are usually red, rose or white. The varieties with bronze leaves are more sun tolerant than the green-leaved varieties. Begonias have to have well-drained soil. Tuberous begonias have much larger, slightly hairy leaves and large, bold flowers. They grow from a bulb/tuber; require shade in the afternoon, frequent feeding and well- drained soil.
Celosia These plants can be divided into those that have fine, feathery flowers called plumes and those that have ruffled, crested flowers called cockscombs. There are varieties that are short and used for bedding and others that are tall and used for cutting. Celosias all need full sun to do their best and prefer rich, well drained soil. Celosia blooms are usually in strong bold colors such as red, orange and yellow. Celosia flowers are also valued because they hold their color and form for weeks before fading.
Coleus Prized for its colored foliage and its ability to grow well in the shade. There are also some new types of coleus that are vegetatively propagated called Sun Coleus. Coleus will grow in almost any soil type and does well in our climate in any situation with bright light. The leaves are usually a combination of colors, mostly shades of red, green, silver and orange.
Dusty Miller This plant provides soft gray, almost white leaves that help show off other plants. In addition to those with bold, white leaves, and look for the fine, feathery varieties that offer a more subtle contrast. Dusty miller does its best in full sun but will tolerate light shade too. Most varieties grow 8-12 inches tall.
Dianthus Annual dianthuses are the cold-tolerant cousins of carnations and pinks. Flowers can be single or double and the delicate petals are often fringed. They tend to do their best very early in the season and fade as the summer gets hot, just like pansies. Annual dianthus can be pink, white, pale purple or rosy red. They are slightly fragrant. Grow dianthus where they will get lots of strong light and in well-drained soil.
Impatiens These are the queens of all the shade annuals. They don’t require any direct sun and will bloom wherever there is strong light. Impatiens is valued for their wide color range and ability to bloom consistently throughout the season. Fertilize them regularly and pinch them if they get too tall or leggy. There are several types of impatiens offered in garden centers. Look carefully at the tags to make sure you are getting the size plant you want as well as the color.
Lobelia hese plants are best known for their masses of delicate flowers with intense blue color, but there are also rose and white varieties available too. Like pansies and dianthus, lobelias like the cool part of the season. Plant them where the will get full sun in spring and some shade as the trees leaf out and the summer heats up. Watch for the trailing or cascading varieties as well as the upright, mound-forming ones.
Moss Roses Known by their botanical name Portulaca, are true sun lovers. They are low-growing plants, almost forming a mat. The flowers are fairly large and offer many bold colors. Plant them where they will get full sun and have well-drained soil.
Petunia Here is an old-fashioned annual that continues to be popular and has been rejuvenated by new varieties.
Petunias offer large flowers and lots of colors. Petunias do their best in full sun but will tolerate light shade (But they will bloom a little less). They need well-drained soil and should be fertilized regularly. New varieties such as the Wave petunias need to be fertilized constantly to keep them in full bloom.
Salvia There are a couple of types of salvia used as annuals in our climate. The standard, garden sage, Salvia splendens, offers large flowers in bold colors, typically red or purple. For a good blue, we also grow Salvia farinacea. Occasionally you will see Salvia coccinea offered too. It is a taller, more open plant that has more delicate blooms in pink, red or white. All salvia does best in full sun but the garden sage will also tolerate light shade. When selecting salvia for the garden, be sure to check the tags for information on plant height. Salvias should be deadheaded and fertilized regularly to keep them blooming.
Verbena This is another annual that has undergone great changes in resent years. New varieties are now much easier to grow and more resistant to powdery mildew than older types. Verbena has tight clusters of small flowers and comes in a wide range of colors. Some varieties are trailing others are mound forming. Verbenas do best in full sun.
Vinca An annual that is incredible when we have a hot, sunny summer and struggles when we don’t. It offers large flowers of white, pink, pale purple and rosy-red. Plant it in full sun and well-drained soil.
Zinnias They come in a wide variety of plant heights and colors. All the flowers are daisy-like but they can be singles, doubles, cactus or other forms. Colors tend towards orange, red, yellow and pink. Flower size may range from less than an inch to 4 or 5 inches across. Zinnias prefer full sun and well-drained soil. Look for the new Profusion zinnias and the thread-leaf varieties that are the most disease resistant.
Additional Bachman's Information
Petunias, Old and New
Geraniums: Zonal, Seed and Ivy
Annuals for the Shade
Fertilizing Annuals and Perennials
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