We're not talking "glamping" where you have structures with beds, running water, and electrical outlets. This is sleeping outdoors in raw land, starting fires from scratch, and setting up tents. When you go with a group, there are assigned responsibilities and everyone looks out for each other. We will often have to hike miles and miles just to get to the camp site and once there, there isn't a sign that says, "Camp here". This is camping and it's awesome!
Mid-weight merino wool or synthetic baselayer (1 if you run hot, 2 if you run cold). Baselayers are the tops closest to your skin.
Midlayer, such as a sweater or puffy jacket. Down puffy if you run hot, synthetic puffy if you run cold (or if you're a vegan.
Outer layer, a shell like a rain jacket if you run cold and/or insulated, water proof/resistant jacket. It does rain in the spring.
No big, heavy coats, because they're not easy to pack in your bag and too heavy to lug around.
You can start wearing shorts now.
Cotton pants are OK. Cords or denim not recommended.
Sturdy sneakers or hiking boots.
Flashlight (because it gets dark earlier, this is recommended as standard).
Bug repellent (like DEET).
Tent (you can rent or share with others who bring)
Sleeping pad. There are different varieties, but they all make a huge difference between a good night's sleep or a bad one.
Sleeping bag. Don't be cheap. The comfier and lighter, the better. But you won't always need it.
Optional: fleece blanket. It's extra weight, but if you don't have a fancy sleeping bag and/or pad, I find this is a good substitute.
Trekking poles or walking sticks you pick up in the woods. They really help with underpronated walkers. (If you don't know what you are, I can tell you if you come out on a trip.)
Flashlights, headlights, lanterns, with extra batteries.
13-gallon (or greater) trash bag (it's multi-purpose and can be used in a variety of ways).
Optional: camp stove and kitchen set. Although this ads weight and complexity to your packing, it's worth having as a stand-by.
BPA-free, 1-leter water bottles (such as Nalgene). They can hold more than just water and are virtually indestructible.