Nothing OUTSIDE, except empty soiled bedding.
I transplanted DH's beefsteak heirloom tomato seedlings. They were started in a 12 cell greenhouse in jiffy pots. Practically every single seed and ALL of the extras germinated--not ready to to practice any "Hunger Games" reaping on them YET!
I put each jiffy pot and 1 1/2" tall seedling into a bigger pot. I bought those 5 inch deep, ~4 inch diameter recycled materials (probably newspaper and sawdust) pots, filled with starter soil over the top and 1/2 way up each stem to stabilize it, watered, then put a 1-2" plastic or styrofoam dish underneath, and filled the dishes with water, so I can water underneath. These I put inside a 10 inch x 4 foot plastic window planter, and put THAT on top of a piece of wood secured on top of a radiator. This is all by a south facing window that has a storm window on the outside. I know that the radiator will provide heat and they'll get all day sun.
It's right next to our dining room table. We won't forget to water them (from underneath) there. As they get taller I will fill in with starter soil. I've been thinking about starting tomato plants like this since last Fall!!!!
I also started lettuce in two quart sized plastic water bottles and a reused, plastic, Q-Tip container with a plastic bag around it for a greenhouse. All the lettuces are now on the south window of my east facing, enclosed porch. (It's like how apartment dwellers are growing lettuce in soda bottles in their windows.)
Now I can work all week and check on their growth all next weekend without watering!!