What should I look for when buying annual flower and vegetable plants?

FAQ
Question: 

What should I look for when buying annual flower and vegetable plants?

Answer: 

Select short, stocky plants with dark green foliage.  Avoid tall, spindly plants.  Small to medium-sized transplants become established in the garden more quickly than large ones.  Short, stocky vegetable transplants are often more productive than large plants with flowers or fruits.  When selecting annual flower and vegetable plants, large transplants are usually not the best choice.