Do annual flower and vegetable plants need any special care before planting?

FAQ
Question: 

Do annual flower and vegetable plants need any special care before planting?

Answer: 

Annual flower and vegetable plants started indoors or purchased from greenhouses should not be planted directly into the garden.  The intense sun and strong winds may damage or kill the tender transplants.  Plants should be “hardened” (acclimated to outdoor growing conditions) before transplanting them into the garden.  Initially place the plants in a shady, protected site.  Then gradually expose the plants to longer periods of direct sun.  Closely watch the plants during this period.  Check on them at least once or twice a day.  Thoroughly water the transplants when the soil surface becomes dry to the touch.  Move the plants indoors if strong winds, a severe storm, or an overnight frost threatens them.  Transplants should be ready to plant after 6 or 7 days of hardening.