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GARDENING TODAY: GERANIUMS

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Geraniums
The popular geranium is one of the most versatile plants grown. It is equally effective when grown in borders, in mass display, window boxes, planters, or as a house-plant. The huge variety of leaf forms and flower colors makes its inclusion in the garden a must. Geraniums can be successfully mixed with garden perennials and annuals for sure color additions or grouped with other plants in patio pots.

Zonal Geraniums
Zonal geraniums are so named because of the zoned horse-shoe-shaped markings on the leaves. Two different types of zonal geraniums exist differentiated by their method of propagation. The two basic types are:

Cutting geraniums which are generally propagated by "cuttings". They are usually tall plants which bloom early on large, round flower heads.
Seedling geraniums which are grown from seed. They are generally shorter, bloom later in the season, and work especially well when massed in annual garden beds.

Planting
Don't be in a hurry to set geraniums out-doors in the spring. Make sure the soil has had a chance to warm up. If the plants have come directly from a greenhouse, they may be tender. Harden them off by setting them outside (in their pots) for several days before planting.

Soil Preparation
Flower Beds
Spade the soil deeply. Amend soil with peat moss or composted ground bark, if necessary.

Patio Pots and Containers
Fill with moistened, commercial potting soil. Never use straight garden soil, since it will not provide adequate drainage and may carry weed seeds, as well.

How to Plant
Remove each geranium from its container, making sure that the plant is not pulled away from the root ball. Gently tear and loosen the roots at the bottom of the root ball. Plant the root ball at, or slightly below, the soil line.

Light - Full sun

Watering - Water thoroughly after planting and whenever the soil begins to dry. Water early in the day. Instead of sprinkling the foliage, try soaking the ground around the plants.

Fertilization - Granular high-phosphorous fertilizer may be added to the soil at planting time. Water-soluble fertilizer, such as 'Miracle-Gro' can be applied at regular intervals throughout the summer. Or, apply a slow release granular fertilizer such as 'Osmocote' once every 4-6 weeks for continuous fertilization.

Maintenance - Remove faded blooms by snapping the flower stem off near the base. Pinch back long stems occasionally to encourage more branching and promote bushier plants.

Martha Washington Geraniums
Martha Washington Geraniums are grown for their large, colorful flowers which are often bi-colored with decorative streaks through the petals.

Light - 'Marthas' grow and flower best under cool conditions, which can be difficult to provide during our hot Montana summers. For this reason, it is suggested that they are grown in filtered light. During the spring, when nights are cool but not freezing, they will thrive in full sun. Martha Washington geraniums require a night temperature of 50-60 degrees F. in order to set flower buds.

Watering - 'Marthas' grow best when the soil is kept evenly moist. Water early in the day, soaking the ground thoroughly.

Maintenance - Occasionally remove faded blooms. If you plan to keep the plant through the winter, pinch back all stems before taking indoors.

Ivy Geraniums
Ivy Geraniums are named for their ivy-shaped leaves and trailing growth habit. They make attractive hanging baskets or flowering groundcovers.

Light - Though Ivy Geraniums generally prefer a shadier location with cooler temperatures than Zonal Geraniums, some of the new hybrids will tolerate warmer, sunnier conditions. The smaller-flowering ivy geranium hybrids make great bedding plants when massed together in an annual planting bed in full or part-sun.

Watering - Keep ivy geraniums grown in hanging baskets evenly moist. During the heat of the summer, you may need to water the baskets every day. Ivy geraniums grown as flowering groundcovers should be kept moist but not water-logged. Keeping the soil moist also keeps the roots cooler.

Maintenance - Remove faded blooms. Pinch back long stems occasionally to encourage more branching.

Scented Geraniums
These species of geranium produce less showy flowers and are grown primarily for their fragrant leaves. Many varieties can be used as flavorings in cooking or for making fragrant dried potpourri. Many different scents are available, including lemon, nutmeg, apple, peppermint, and orange.

Light-Full sun
Watering-water thoroughly whenever the soil begins to dry. Water early in the day. Instead of sprinkling the foliage, try soaking the ground around the plants.

Fertilization-Granular high phosphorous fertilizer may be added to the soil at planting time. Water-soluble fertilizer, such as 'Miracle-Gro' can be applied at regular intervals throughout the summer. Or, apply a slow release granular fertilizer such as 'Osmocote' once every 4-6 weeks for continuous fertilization.

Maintenance-Remove faded blooms by snapping the flower stem off near the base. Pinch back long stems occasionally to encourage more branching and promote bushier plants.

Over-Wintering
Before the first frost in the fall, you may want to bring in some of your favorite varieties to survive the winter indoors. The method in which you save these geraniums depends on how much light and space you have available.

1. Take cuttings from your favorite large geraniums, root in small pots of soil covered with humidity-conserving plastic bags or inverted jar. Place in a window with high light. After the cuttings have rooted, water infrequently but thoroughly.

2. Dig up entire plant from garden. Re-pot into a container and place in a window with high light. You may want to prune off one-third to one-half of the plants newest branches, now, or later in the winter when the plant gets too large.

3. Move containers of geraniums to an area which has a temperature of 40-50 degrees F. throughout the winter. Prune back at least half of the plant. Water infrequently. In March, move pots into warmer temperatures and more light. Begin to water more regularly.

4. Dig geraniums from the garden. Trim back to 8-10 inches. Remove soil from the roots with a blast from a garden hose. Wrap in damp newspaper. Enclose each in sealed paper bags. Store in a root cellar or cool area which will not freeze. Remove from bags in March, soak in water for a day, re-pot and place in good light. Water when the surface of the soil appears dry.