What is the name of this cactus? I'm planning to replant it and want to do it properly accordingly to its species.
Echinopsis species. Not so sure about the exact variety. Cactus likes gritty potting mix or well draining medium. Those type of species requires full sun exposure to maintain its shape. They become etoilated when they cannot received enough sunlight. When watering use the "soak and dry" method. When the medium is bone dry, it's the right time to water your plant. Water generously and deeply. Every quarter you can feed them nutrients. Complete fertilizer suitable for cactus is available online. Hope it helps.