Herb of the Year: Scented Geraniums

The International Herb Association has proclaimed scented geraniums,

Pelargonium, as the 2006 Herb of the Year. Name a fragrance, and there is probably a scented geranium to match: rose, lemon, orange, lime, strawberry, peppermint, nutmeg, apple, apricot, coconut, camphor, and the list goes on.

Because of their fragrance, ease of growing and decorative foliage, they have been a favorite addition to the garden for hundreds of years. Scented geraniums are native to South Africa and were introduced into Europe in the early 1600s. Today there are approximately 280 species of Pelargonium.

Scented geraniums are grown for the scent in their leaves; thus, the plants are named for their fragrance. Their aroma can be released by breezes, by rain or by lightly rubbing the leaves. This group of plants is noted for its great variety of leaf shapes and patterns. Leaf shapes range from rounded to finely cut lobes, and texture can be smooth or fuzzy.

Scented geraniums are effective as ornamentals in the landscape, grouped in containers or shaped into topiaries. Some have attractive

blossoms, but most scented geraniums have flowers with little impact. The small flowers grow in clusters, and colors range from white to shades of lilac and pink.

Most varieties of scented geraniums are fairly easy to grow and will

survive less than optimum conditions. Plants will perform the best in full sun. However, during hot, dry summers, plants will do best with full morning sun and filtered afternoon sun. Plants prefer a well-drained, evenly moist garden soil with ample organic matter. Good air circulation is essential to ensure healthy growth.

Plants that are not pruned tend to grow long, single leggy stems. As soon as it has at least five nodes or is 4 to 6 inches tall, cut or pinch the growing tips. Remove stem tips above a leaf with scissors or your fingers. This haircut will promote a more compact, bushy plant.

Scented geraniums are considered perennial; however, in most of the United States, they are grown as annuals. To overwinter, plants may be potted and brought in the house. This needs to be done before the first frost when night temperatures are still above 45 degrees. Indoor plants will do best in a south-facing window that gets at least four hours of sunlight per day. Without supplemental indoor light, plants may become leggy during the winter.

In the spring, several weeks before taking plants outdoors, a pruning is in order. You can also root 3- to 6-inch cuttings to start new plants. This is done by

removing the bottom leaves and planting in a lightweight sterile potting media.

Species of scented geraniums vary in their susceptibility to white flies, aphids, mealy bugs and spider mites. Inspect plants regularly to identify any insect or disease problems. Small infestations of these insects can be controlled by a strong spray of water (which dislodges insects) or by using an insecticidal soap.

Leaves of scented geraniums are ideal for potpourri. Although some

varieties are used in food dishes, not all scented geranium varieties have tastes that complement food. Lemon, lime, rose, apple and mint species are most commonly used in sweet dishes such as jellies, punch, cookies, cakes, muffins, teas and ice cream. Most often their flavors are infused in a food dish, and the leaves are removed before

serving. Fresh leaves can also be used as a decorative garnish.

Scented geraniums have a unique range of attributes, making it

a great addition to the house or garden.

Spring Gardening Tips

Spring is here .... lawns green up, bulbs emerge and bloom, tree buds swell, and many of our garden "friends" start to poke through the mulch. Here are some things that can be done now:

F Clean up garden beds. Rake out any leaves that may have collected over the winter. Leaves often will matt down and cause soils to remain too moist this time of year. Put them aside to be used in your compost all summer long. Cut back remains of perennials now. Remove what's left of last year's annuals.

F Fertilize your bulbs. Any 1:1:1 fertilizer such as 10-10-10 or

5-5-5 will do. Now is a good time because you know where they are! Also, the recommended time is

between emergence and before flower bloom.

F If the soil is not too wet, work up your vegetable garden to help the soil warm up. Add some compost, aged manure or peat moss as you work the soil. Also, this is a good time to add a 1:1:1 ratio fertilizer and work everything in at the

same time.

F Plant potatoes, beets, peas, cabbage, spinach, lettuce, onions and radishes now. These are cool- season vegetables that do well in the early spring temperatures.

Listen to weather reports for any freeze warnings. The average date of the last frost in southern Illinois is April 15; in central Illinois, it is April 25. This means there is a 50 percent chance of a freeze that would kill tender vegetables.

F Start seeds indoors. Many

annuals and summer vegetables can get a head start if they are planted indoors now. You need a bright area or grow lights set 1 to 2 inches above the seedlings to insure short stocky plants.

F Remove mulch from strawberries and, if necessary, apply a weed control. Read and follow all label directions.

F Prune summer-flowering plants such as Hydrangea, Potentilla and Rose-of-Sharon. Don't prune spring bloomers such as Lilac, Weigelia or Mock Orange. If spring bloomers are pruned now, you are cutting off the flower buds. Cut back Buddleia and Caryopteris. Start to remove any plastic coverings, such as rose cones, as the days get warmer.

F Fertilize perennials, shrubs and trees.

F A pre-emergent herbicide for crabgrass should be put down by mid- to late April. Crabgrass is an annual, and it just needs soil

temperatures at 50 degrees for three to five days to sprout. Once it has germinated, a post-emergent herbicide is needed.

Fireblight: Serious Disease for Apple and Pear Trees

Fire blight, caused by the bacterium Erwinia amylovora, is a common and potentially serious plant disease specific to the family Rosaceae. The disease is also referred to as

blossom blight, shoot blight, twig blight, spur blight, fruit blight or rootstock blight, depending on the plant part that is infected. Fire blight most commonly affects apple and pear trees, but it can also affect other rose family members such as spirea, mountain ash,

raspberries and blackberries, cinquefoil, quince, hawthorn and cotoneaster.

Fire blight gets its name because infected trees appear as if they have been scorched with fire. Shoots infected with fire blight can be identified by the characteristic "shepherd's hook" on the tip. Death can result from severe infections of fire blight, especially on younger trees and trees grown on fire blight susceptible rootstocks. In most cases, fire blight will not kill an apple or pear tree; but trees can become unsightly, and yields can be reduced.

Three conditions are necessary for the development of fire blight–the presence of the pathogen, moist conditions, and a high temperature.

The fire blight bacteria overwinters in cankers formed from the previous year and resumes growth in the spring when favorable conditions are reached. Fire blight enters the plant tissue through natural openings and wounds created by insects, storm damage and mechanical injury. Favorable conditions include rain, heavy dews or high humidity in combination with an optimum temperature range of 65 to 86 degrees. Without favorable conditions, infection does not proceed.

Some apple and pear varieties are more susceptible to fire blight than others. Below is a partial listing of the more common cultivars and their relative resistance to fire blight. Use this information when selecting an apple or pear tree for planting.

What can you do if a tree develops fire blight? Fire blight can be

unsightly when trees are heavily

infected, and many growers feel the need to remove the infected plant parts. But, it is best to delay the removal of infected shoots until the dormant season to avoid spreading the infection to healthy shoots. In addition, summer pruning

promotes new growth which is

more susceptible to fire blight.

If pruning cannot be avoided, wait for dry weather when conditions are less conducive to infection spread. Always make the pruning cuts at least 6 inches below the last point of visible infection. And, sterilize the pruning shears between each cut by dipping them in 1 part liquid bleach to 4 parts water.

Avoid over-fertilization of apples and pears because this practice also promotes lush, green growth which is highly susceptible to fire blight. Pears are generally more susceptible to fire blight than apples. For this reason, fertilization is generally not recommended unless the tree demonstrates a nutritional need through reduced growth or yield.

Another line of defense against fire blight is chemical control. One option is Bordeaux mixture applied during the dormant stage to further reduce the inoculum level. Another option is the use of agricultural streptomycin labeled for apples and pears. Agricultural streptomycin can be applied during critical periods occurring between bloom and petal fall.

For more detailed information on symptoms, disease cycle and control of fire blight, visit:

http://www.ag.uiuc.edu/~vista/abstracts/a801.html

University of Illinois~U.S. Department of Agriculture~Local Extension Councils Cooperating~University of Illinois Extension provides equal opportunities in programs and employment.

If you need special dietary or disability accommodations to participate in any events listed in this newsletter, please contact your local U of I Extension office.

April 2006

Volume 13, Issue 4

Sharon L. Kuhns

County Extension Director

Coles County

707 Windsor Rd, Suite A

Charleston IL 61920

(217)345-7034

Coles_co@extension.uiuc.edu

Helping you put knowledge to work.

Articles written by U of I Extension horticulture staff: Martha Smith, David Robson and Elizabeth Wahle

In this Issue

Herb of the Year

Spring Gardening Tips

Fireblight: Serious

Disease for Apple and Pear Tree

Cultivar Resistance to Fire Blight

Highly Susceptible

Apple – Braeburn, Cortland, Fuji, Gala, Jonathon, Lodi,

Rome Beauty, Winter Banana

Pear – Anjou, Bartlett, Bosc, Red Bartlett, Starkrimson

Moderately Susceptible

Apple – Empire, Golden Delicious, Granny Smith, Jerseymac,

Jonafree, Jonagold, Jonamac, McIntosh, Mutsu, Spartan, Stayman

Pear – Maxine, Seckel

Moderately Resistant

Apple – Delicious, Liberty, Priam, Prima, Priscilla, Redfree, Winesap

Pear – Moonglow, Starkling Delicious

We're on the Web!

web.extension.uiuc.edu/coles/

Hi everyone!

Spring is here---Yea! The daffodils are blooming and the forsythia that I purchased at the Master Gardener plant sales last year survived the winter and is also putting forth beautiful yellow blossoms.

The Master Gardener training is on it's final lap. One class, test/graduation and tour day are all that remain. So, in May there will be four new faces join our group. We will have some special activities to get them acclimated. Be sure to wear your nametag for the next several meetings. It really helps them learn names. The trainees and mentors have had their first meeting and will meet again in late April. I'm really please with the mentoring program you have established–it seems to be better every year. Thank you to Susan H, Kathy H, Max and Joyce for serving as this year's mentors. And, Phyllis is on stand-by if the assigned mentor isn't available to answer questions.

Herb Fest is just around the corner. I've been hearing you discuss what you are planting, digging, thinning, etc., in preparation for the annual sale. Be sure to tell your gardening friends about the event and where our booth is located. All proceeds from the day will benefit the U of I Extension Ag and Natural Resources programs in Coles County.

Jim Schuster is making his annual Road Trip again this year. He will be in Coles County on May 4^th. Registration details will be at the meeting tonight. Remember, we must have 15 in attendance to stay on his annual schedule. This training is open to others in the horticulture field. So, if you have friends or neighbors who are employed in a related field, please share the information with them.

You can order Master Gardener apparel NOW. Spring is the only time of year to place an order, so check out the latest Imagine newsletter for the order form. Please turn in the order and check to the Extension Office by Friday, April 14. The apparel usually arrives in early June, so you will need to be patient.

The annual 4-H BBQ is this weekend. I hope to see many of you there supporting our youth program and enjoying a delicious meal!

Sincerely,

Sharon

Sharon L. Kuhns

County Extension Director

- Martha Smith, David Robson, and Elizabeth Wahle