I am not keen on flowers indoors, but confess to a weakness for the amaryllis bulbs that you plant in a pot and bring into bloom within a few weeks.
They are not correctly called amaryllis at all, but that's what dealers call them, and that's what you get when you ask for them in nurseries or garden centers or places where they sell garden stuff.
Correctly they are Hippeastrum, which I suppose means "horse stars," and since the lily-like flowers are vaguely star-shaped, and since they are large (and anything large or coarse is likely to have the adjective "horse" applied to it) I guess the name is all right. You can see, probably, that horse-star is somehow not as pretty a name as amaryllis, and that is why nurserymen don't call them horse-stars, possibly.
Confusion sometimes arises since other bulbs are also called amaryllis. The hardy bulbs that flower in summer on tall stems, without any leaves accompanying them, are Lycoris radiata, sometimes called Amaryllis hallii. In my country they were called naked ladies, since the flower stalks come up out of bare earth without any leaves then. (The leaves die down before the flowers appear.)
The hippeastrums are not hardy outdoors here, and must be grown in pots in the house, but the naked ladies are perfectly hardy, and pretty with their whorl of pink lily-like flowers, scented, and much admired for cutting.
There is yet another amaryllis properly entitled to the name, and this is Amaryllis belladonna. Its flowers are larger than those of the Lycoris, but not so large as the Hippeastrum. Unfortunately, it is doubtfully hardy; I have lost the plants several times, but if you wish to try them, give them a sunny spot at the foot of a wall facing south. They bloom in late summer or early fall, but the leaves appear as the flowers die down, and these leaves are often damaged by ice in the winter months. They die down in the spring, and no sign of life is seen until the naked flower stems appear toward Labor Day.
But the plant now growing happily in pots across America, and which we all call amaryllis, is the quite tender Hippeastrum, and I mention all this because you do not want to plant it outdoors until summer.
The Dutch make a specialty of these bulbs, as they do of so many plants from South Africa, and it is wonderful that one can plant a leafless bulb in a pot now and have it in bloom within a few weeks.
Usually there is one stalk bearing four flowers, in white, pink, red or orange, and sometimes striped -- there are many named varieties. After flowering, the leaves continue to grow. It is critically important for the pot to be watered and given as much sun as possible, after the flowers fade. Do not neglect it, as the performance of the bulb next year depends on how well the leaves grow following its flowering this year.
By mid-May it is safe to set the pots outdoors, to continue growing leaves all summer. It is best to take the bulb out of the pot and plant it (with its growing leaves) in a sunny spot in the garden, but if there is no space for this, the bulb can be left year-round in its pot.
The critical thing is for it to develop its leaves after flowering, whether in a pot or in the open garden. It is brought indoors by October, and the process starts again. I have a few of these bulbs that have performed well for the past 10 years, with sometimes haphazard care.