Very little watering between the sowing of the seed and the emergence of seedlings is required if done properly. Plants raised in boxes although "adequate" have proven to be inferior to those raised in pots or soil blocks.
Be sure to give the seedlings room to expand. Close conditions will inhibit their growth. Transplant them to a larger pot as soon as they get several true leaves, and if need be, move them into larger pots about two weeks after that.
Transplanting Your Seedlings Outdoors
Transplanting your seedlings outdoors at the proper time is critical . If done too soon , they may not survive or properly acclimate to the outdoor environment. If you wait too long, they become 'pot bound' and may not be able to adapt properly either. See Frost Dates
Counting the number of 'true leaves' is one of best ways to tell if a plant is ready to go out into the real world.
Place seedlings outdoors in their original containers where they will receive direct sunlight and some wind for a few hours each day for a week, possibly more. Gradually lengthen the amount of time outside each day. Move the plants inside at night. See - Hardening Off Seedlings
Check the Frost Dates for the best Best Planting time for your particular crops and regions.
For about a week before transplanting your seedlings outdoors
Do not Fertilize
Cut back on the watering
Harden your seedlings, gradually forcing them to acclimate or adjust to the outdoor climate
You can 'harden' by setting your seedlings outdoors in a somewhat shaded /Partly sunny area that is protected from high winds for several hours daily, gradually increase this time in an outdoor environment . The soil should be moist, but not saturated during the hardening-off period.
If possible, transplant on overcast days , early morning is best.
Put the seedlings into well aerated loose moisture retentive , well draining soil. The soil should allow for easy expansion of the root system. Generously spreading mulch around the seedlings will help with moisture and heat retention. Plastic mulch helps best with retaining warmth.
Water the new seedlings immediately after transplanting.
Be sure the proper nutrients are present, phosphorus aids development of the root system and should be in whatever starter solution is recommended for your particular crops - See Understanding Fertilizer Labels.
Thinning - Spacing Vegetable Gardens
Companion Planting Guide
Understanding Fertilizer Labels
Track and Adjust Soil pH