I put a small hole in the bottom of the cups and plastic trays for drainage and put a container or pan underneath so watering is easy by filling bottom and it soaks it up through the holes made. Fred Meyer usually has a great deal on seeds (as pictured previously.) Just follow planting instructions per packet for indoor starts. If the seed packet doesn't specify you can start indoors first, I typically will plant those directly into the garden when it stops frosting at night (later in the Spring). This is just from my personal experience for my climate the last few years. Your area may be more accommodating earlier in the season.
After you have filled the containers with seedling mix soil and put your seeds in (or watered your peat disks so they have expanded and filled the cup), I keep them in a warm area, such as up on top of my refrigerator or near a light. When they start to germinate and pop up a nice sunny spot works great to re-position them to. You can raise the lid as they grow (I usually find a popcicle stick or a chopstick to prop the lid open with and cover the gap with some plastic wrap.)
These squash seedlings popped up quickly in about 6 days. Remember to not let them get too dry but keep moderately moist but too much will cause rot. You may need to re-pot to a larger pot if roots start getting too cramped I have found. I like to acclimate the plants eventually for a short time on my covered deck during the day and bring them in at night for a week or two also before putting them in the vegetable or herb garden.
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