Hippeastrum evansiae:
There aren't many yellow Hippeastrums, and Hippeastrum evansiae is probably the most readily available. It is from Bolivia, and grows in hot, dry conditions. It is rare in the wild, its habitat having being converted to agriculture, but is fairly easy to grow and propagate. There are slight variations in the species, some having a pale orange central star. Mine are greenish in the center. It needs to be kept warm, and I grow mine on my heated benches year round in Mix #1 with some added pumice.
Hippeastrum leonardii:
Hippeastrum leonardii is from Peru, but I am not sure of the conditions it grows in. I am growing mine in Mix #1, and I have pots on my heated benches, and also on the unheated benches. The heated ones have bloomed more reliably, so it seems to need extra heat. I will try to round up more information on this lovely species.
Hippeastrum machupijchensis:
As the name indicates, Hippeastrum machupijchensis hails from the legendary Machu Picchu region in Peru. Machu Picchu itself is around 8000', but the species also grows at lower elevations. Since it is a high elevation species, I have not given it extra heat. It offsets rather slowly, and I have not obtained seed from my bulbs. I grow it in Mix #1, and keep it on the dry side, with 2/3 of the bulbs exposed above the surface of the mix.
Hippeastrum mandoni:
Hippeastrum mandoni is a magnificent species that hails from Bolivia. It is the largest Hippeastrum I grow, the flower stems reaching up to 30" and mature bulbs reaching 6-8" in diameter. It needs a large pot, and I grow it in deep five gallon pots in Mix #1. I do not give this species extra heat, and it has not been difficult to grow and flower. I do keep seedlings on the mats for the first year, and they mature faster that way.
Hippeastrum macbridei:
Hippeastrum macbridei is another yellow species that comes from Peru. I have no information on it, and my bulbs were acquired as very tiny offsets and have not bloomed yet, so I have no tempting pictures. I am keeping them on the heated benches and they seem happy. They are dormant in winter.