Figure out when you want your amaryllis to bloom. Bring inside to a cool location in late August if you want holiday flowers. Otherwise, wait until late October or before more than a light frost appears in the forecast.
Place your amaryllis in a spot where you can leave the light low around the holidays. Basements work well because of the dim light and cool temperature.
Keep your amaryllis in temperatures of 50 to 60 degrees Fahrenheit. Leave the plant in this climate for 8 to 10 weeks, according to Iowa State University.
Add only a bit of water during the plant's dormant phase, enough to keep the plant from dying. Avoid watering the portion of the bulb sticking out of the dirt. You only want to apply moisture to the soil and the bulb that's within the plant foot.
Cut the flower's stalk right below the top of your amaryllis bulb. Wait until after the bloom on your flower fades.
Move the amaryllis bulb to another pot with fresh soil once you bring your plant out of its dormancy phase. Plant the bulb in a pot no larger than twice its diameter. Cover amaryllis bulb with soil until 1/3 of the bulb shows above the dirt.
Move your amaryllis to a spot with a south-facing window or inside a sunny greenhouse during late February or early March until the last threat of frost has past. Find a spot with a temperature range of 70 to 80 degrees Fahrenheit to encourage leaf production at the same time the plant's flower stalk emerges.
Fertilize once a month using a liquid fertilizer to encourage growth of your amaryllis plant. You want to set your plant up this season to produce flowers during the following year, according to the National Arboretum website.
Water enough that the soil doesn't completely dry out.
Place your amaryllis outdoors as soon as the last threat of frost passes your area.
Set plant in an area that receives plenty of sun, including well-lit porches, decks and balconies.
Fertilize amaryllis every two weeks. Apply a low-nitrogen, slow-release fertilizer or liquid plant food.
Water your amaryllis every day while you keep the plant outside.