Overwatering can cause succulent plant death. This could also result in a dead plant. This plant can grow up to 2 feet tall and 2 feet wide in sunny and warm climates. With a south or west-facing window, you'll likely need to place your succulent a few feet away, but you may be able to keep your String of Hearts directly in a north or east-facing window. Lithops do not require a lot of fertilizer. However, you can give them a small amount every few months to make them stronger and healthier. Even if the summer months are not here, the aeoniums will experience the same dormancy.