Ground Cloth
One of the most important items to tote when tent camping is a ground cloth, which is a waterproof piece of material that gets placed between the floor of the tent and the ground. This thin piece of plastic not only acts as an effective vapor barrier, but it also is capable of preventing wear and tear on the bottom of the tent. In an emergency, a poncho can serve as a ground cloth, but don't plan on using your only piece of rain gear as a ground cloth. If it rains, you might need both.
Foam Pad
Another item that is essential when sleeping in a tent is a foam pad that gets placed under the sleeping bag of each camper. Even backpackers carry a thin piece of special insulation that not only provides some extra comfort, but more importantly adds much needed insulation while the camper is sleeping. These pads are designed to be super light, while at the same time providing a small space of dead air underneath the camper. Air mattresses are not a good substitute for a foam pad, especially in cold weather.
Tent Stakes
Many campers purchase additional tent stakes to ensure that a tent stays erect during adverse conditions. These adverse conditions are not limited to stormy weather: Rocky ground, a sandy beach or deep snow also can present a challenge to the camper. In the case of rocky soil, stainless steel or titanium tent stakes are required to penetrate the hard soil substrate. However, deep snow and soft sand require the construction of "deadman anchors" that get buried deep in the soft substrate. In this type of tent setup, twice the number of tent pegs are needed because each anchor is actually two tent stakes, which are crossed at a right angle and buried in the soft substrate. With these type of anchors the cheaper, plastic stakes will work.
Tent Fly
The rain fly often comes with the purchase of a high-quality tent, but this exterior piece of plastic does more than just add another waterproof layer of protection. The rain fly also can protect your tent from UV radiation and it adds an extra layer of insulation. When correctly designed and properly installed, a rain fly should be separated from the main tent with a 1/2 inch or less of air space. The continuous gap provides some insulation and prevents condensation from forming on the inside of the tent.
Extra Amenities
Extra amenities may include rope, a mallet, a repair kit and a shovel for use in sand and snow.