Lettuce is easy from seed - doesn't like heat (it will bolt to seed quickly) - you can grow it in containers or in the soil. Either way, sprinkle some seed thinly, barely cover, gently water - it will germinate quickly - thin to a few inches between plants. You may want to think of it is as a fall/winter crop. Here in NC I start seeds indoors, move the seedlings into the garden in March - by June and 80 degree days, it is done....it can be planted again late summer to grow into the winter - hard frost kills it.
Tomatoes - plant them deep in a place where the soil drains well. Tomatoes in good soil are like weeds....if they are tall growing (indeterminate), they will get to 8 feet tall or more - even at 3 feet apart they become pretty massive - and closer planting will need suckering (removal of sideshoots) to control the plant. All sorts of diseases and pests go after tomatoes....
Peppers should be started now, in light soilless mix - barely covered - it takes about 4 weeks to go from seed to a seedling that can be transplanted into a 4 inch pot, then another month until it is ready to go into the garden. Peppers thrive in containers - they get 3 feet tall, need support of a central stake or cage.
Check out my YouTube channel (nctomatoman) for all sorts of gardening vids, including how I start my seeds.....
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