Fall is the prime time for planting hardy, spring-flowering bulbs
. Bulbs and perennials need plenty of water and good drainage. If water tends to stand in your planting area, you'll want to break up hard subsoil and put in a layer of drainage material such as coarse gravel, broken stone or sifted cinders below your surface soil.
Summer-blooming Dutch bulbs and perennials
are not fussy about soil, provided it is not too heavy or sticky. If soil is heavy, loosen it with lots of humus, sand or gypsum. If very light, add moisture holders such as humus or peat moss. If you have soil with a high clay content, it can be improved by adding compost, peat moss or some other organic material. The organic material should be worked into at least the top 30 cm of soil and preferably the top 45 cm.