Prepare the planter's soil before planting by mixing compost or other organic matter with your native soil. The raised planter should be in a sunny location.
Plant seeds according to the package instructions. Planting depth, seed spacing and planting month will vary among the many different garden fruits and vegetables, and it is important to follow these directions. In general, early season crops such as lettuce, broccoli, cauliflower, beets, carrots, peas and kale can be planted anytime after the last frost when the ground is workable. Other crops, such as vine crops, require warmer temperatures to germinate. Small seeds are generally planted at a depth of 1/4 to 1/2 inch while larger seeds are planted at depths between 1 and 1 1/2 inches.
Irrigate often once your seeds are planted. You may need to check the soil two or three times a day if you plant in a raised planter. If the soil dries out, your seeds may die and won't germinate.
Irrigate established seedling less often. Usually once the first set of true leaves appear you can cut back to once a day. Eventually, when the plants are fully mature, you'll be able to give them just 1 inch of water a week.