ANNUALS
Introduction
Plant Selection
Hardy, Semi-hardy, Tender
Heat and Drought Tolerant
Shade Tolerant Annuals
Fragrant Annuals
Ornamental Foliage
Climbing Annuals
Hanging Baskets
Cut Flowers
Planting
Starting Plants
Maintenance
Insects Problems
Disease Problems

PERENNIALS
Introduction
Plant Selection
Plant Dimension Characteristics
Specific Site Conditions
Classification by Bloom Periods
Perennials That Attract Wildlife
Planting
Starting Plants
Care and Maintenance

BULB FLOWERS
Introduction
Plant Selection
Planting Bulbs
Purchasing Bulbs
Care & Maintenance

ORNAMENTAL GRASSES
Introduction
Plant Selection
Mature Size
Grasses for Specific Uses
Planting Ornamental Grasses
Obtaining Plants
Care & Maintenance

CONTAINER GARDENING
Introduction
Container Selection
Soil Mixes
Container Placement
Plant Selection
Plant Care

Planting Perennials

 
Perennial weeds must be controlled before planting

Site Selection and Preparation

Proper site selection is critical for success with perennials. Because the plants will reside in the same place for many years, they must be adapted to conditions where planted. If not, they may never reach their full potential for beauty in the landscape.

Major soil preparation in a perennial bed is completed only one time, just prior to planting. Consequently, to avoid future difficulties it must be done properly to ensure a healthy environment. First, kill and remove any persistent weeds and grass. Such weeds are difficult to manage once the beds are planted. This may take several months and multiple applications of a systemic herbicide. Next, make sure the site has good quality topsoil. This may require addition of topsoil, particularly in new home sites. Amend the soil by adding 2-3 inches of well-aged compost or manure. This is especially important in the arid, calcareous soils of southern Idaho. Add a complete fertilizer such as 5-10-5 at the equivalent of 3 lb/1000 sq. ft. of nitrogen. The fertilizer choice should be high in phosphorus and should preferably include sulfur in southern Idaho.

After amendments are added, the soil should be tilled to a depth of at least 8 inches, leveled, and smoothed (but not packed). Just prior to, or immediately after, planting it is a good idea to add two or three inches of mulch (wood chips, bark, etc.) to the soil surface. It may also pay dividends to place some type of edging or border material around the bed to slow encroachment of grasses or other weeds.

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