This results in the appearance of many unwanted seedlings the following spring. Annual weeds complete their life cycle within one year. They set seed that germinates freely. Some will produce several generations in a single season. It is important then to remove annual weeds before they flower and set seed.
Perennial weeds survive from one year to the next.
Many perennial weeds are able to become prolific because of poor cultivation techniques that leave small pieces of the rhizome in the soil after digging or rototilling. One can accomplish this in two main ways. Weeds may be discouraged from growing by using good gardening techniques or weeds may be removed manually, mechanically or chemically. The choice depends upon various factors. One must consider the growth habit and the actual location of the weeds.