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Lithops~Living Stones:
Water/Fertilizer: Allow soil to dry completely between infrequent, light waterings (approximately every three weeks), during the summer dormant periods, (June though August). Water may be given more frequently the rest of the year, however, ALWAYS allow soil to fully dry out between waterings. The amount of time it takes for drying varies, depending on your humidity, light, temperatures, etc., you must use your judgment. Fertilize monthly while
growing, at half-strength. No Fertilizer while dormant. A general, all-purpose, household fertilizer work just fine.
Temperature/Light: These plants do best in average to warm temperatures (65-90 degrees F) and in bright light, possibly near a south or east facing window.
Soil: Must be well-draining; also be sure the pot used has drain holes. For dry climates, use one part sand, one part forest or bark mulch and two parts pumice (or perlite). In more humid climates, less sand is recommended.