An old friend, a priest who lived in on the grounds of a hospital/monestary complex, he has since passed, taught me how to grow the common florist's Amarylis = Hippeastrum hybrids. The dormant season is usually November through to sometime in February. After flowering, and after last frost, he used to plant the bulbs out in his vegetable garden for the summer. He had a whole row of Hippeastrum, between the beans and the corn. After a light frost or two, just enough to wilt off most of the leaves he'd dig them up. cut the leaves short, and store them bare root in a cardboard box. The box was stored inside, at normal household temps. Beginning in January he'd start potting them up in dry soil. Put them in a pot, only bury the bulb half way, keep the neck of the bulb well exposed. Don't water the soil, leave it bone dry. Set on a warm sunny windowsill. In a few weeks you will see the leaves and flower bud start to poke up. Resist the urge to water. Wait until the flower bud is out of the neck of the bulb. Now its time to water. He would then distribute the pots of Hippeastrum all through the corridors of the hospital and nursing home. He had hundreds, but at most 3 color varieties.
If you water them too soon the leaves of the bulb swell, tightening the neck of the bulb. Modern Hippeastrum flowers are so large and have been bred for shorter flower stems, so that sometime the flower bud get's too large to emerge through the neck of the bulb. So hold off on watering until the widest part of the flower bud is free of the neck of the bulb. Water and sun and fertilizer will keep your bulb happy through out the growing season. Put it outside after flowering and after last frost. The more sun, water and fertilizer you give it the bigger the bulb will get and the more flowers you will get. Feed MUCH heavier than you would an orchid. Figuratively, just pour it on. But only do the heavy fertilizer if it is outside in full sun. Indoors, take it a bit easier. Basically, that's it. You can beef your amarylis up to the point where a single bulb is over 2 pounds (I might be exaggerating), but in 3 -5 years you can have monster big bulbs, which means a more spectacular flower display.
If you do Hippeastrum indoors all year long, just stop watering sometime between Halloween and Thanksgiving. After the soil is dry, chop off the old leaves, even if they have not wilted yet, just go ahead and cut them off. If the soil does not get bone dry within a couple weeks, knock the bulb out of the pot and store it bare root. Pot up when you see green peaking out of the top of the bulb, usually 12 weeks after bare rooting the plant. The dry rest causes the flower bud to initiate.
Smaller bulbs may not have the energy to put out a flower, just begin the water and fertilizer when the new leaves start to show. Big bulbs often offset little bulblets. You can let them form a clump or you can separate them.
You can also work out the timing. Number of days from the time you start watering until flowering. Its either 4 or 6 weeks. Then you can force the bulbs to bloom for specific dates. Figure 12 weeks dry and 6 weeks to full bloom, so 18 weeks before the target date bare root and remove old leaves on the Hippeastrum you want to force. Then pot up about 6 weeks before the target date, lightly dampen the soil to make sure your bulb gets the signal to start growing, but then keep dry until flower bud is clear of the neck of the bulb. You should have blooms for your sweetie. Its easy.
