Euphorbia

Some varieties include:  Milii (Crown of Thorns), Coral Cactus (lactea grafted onto neriifolia)  

Light:

Best possible light for all species of Euphorbia in winter.  Succulent varieties can tolerate direct sun all year. Avoid direct summer sun for e. pulcherrima (poinsettia).  

Water: 

Water freely from spring to autumn allowing the soil to dry between waterings. Water sparingly in winter.

Temperature:

Euphorbia will thrive in average indoor temperatures, and outdoors can be grown year-round in U.S.D.A. growing zones 10 and 11, or during the warmer months in temperate zones.

Fertilizer:

Fertilize with a weak (diluted) houseplant fertilizer in summer.  

Potting: 

Repot into a planter with holes for drainage, using a cactus soil mix or a 50/50 combination of regular potting mix and sand. Plant shallowly, just covering the roots. Then press down the soil to anchor the plant and prevent it from leaning or tipping.