The soil at the site must be well drained! This is one of the most critical factors for planting. How does one determine if the site drains well? The easiest method is to observe the proposed planting area the day after an intensive rainfall. If water is standing in the site, then the soil does not drain adequately. Therefore, either another site needs to be selected or the drainage needs to be improved.
Check soil pH of the site! Once drainage in the site has been assessed, test the soil for the pH level. It should be within a range of 6 to 7. If necessary, adjust the pH level.
Check for perennial noxious weeds! Determine if the site contains weeds such as nutsedge (Cyperus spp.), quackgrass (Elytrigia repens), bermudagrass (Cynodon dactylon), or Johnsongrass (Sorghum halepense). If present, they must be eliminated before any ornamental plants, including flower bulbs, are used.
Check for proper light conditions! Depending on the genus, flower bulbs perform optimally under different light conditions. When De Hertogh and Le Nard (Chapter 6, The Physiology of Flower Bulbs, 1993, Elsevier Science Publishers, Amsterdam) reviewed the literature on light requirements for outdoor usage of flower bulbs, they proposed that five classes be used. This system is used in this Bulletin. The five light conditions are defined as follows:
The higher light intensities are preferred for Northern Climatic Zones (3 to 6) and the lower light intensities for Southern Climatic Zones (7 to 11).