At the top of the list for Christmas tree substitutes are Norfolk Island Pines and Rosemary plants. Norfolk Island Pines grow slowly and maintain their shape naturally. These pines like a location where they will receive bright, indirect light. Water your Norfolk pine when the top inch of soil feels dry. Water thoroughly, until water comes out the bottom of the pot.The herb rosemary is a good choice for a table top decoration at Christmas because the leaves are needle-like and the plant is very aromatic. It's easy to prune your rosemary plant in order to keep the pine tree shape. You can buy rosemary in several different sizes ranging from a few inches to several feet tall. For best results, place your rosemary in the sunniest and coolest place you have, usually by a large window. Rosemary likes water so keep the soil moist at all times. Be consistent in your watering. Try to avoid letting the plant dry out and then over watering it. More choices for small table top tree decorating include Lemon Cypress, conifer bonsai plants and ivy topiaries. Lemon Cypress trees have plume-like yellow-green foliage that releases a lemony fragrance to the touch. holiday decorations and will continue to grow after Christmas is over. Another idea for decorating naturally would be to use a conifer bonsai plant. Lack of humidity is generally the biggest problem you'll encounter with Norfolk pines, rosemary and other houseplants as well. You can also use a cool mist room humidifier to increase humidity. Feed these plants every two weeks with Fertilome 20-20-20. Age Old Fish and Seaweed. For best results, supplement with SuperThrive each time you fertilize. These plants will help to decorate and freshen your house long after the holidays are over.