Master the "Rate Sensitivity." Rho measures how changes in interest rates impact your option prices over time.
Rho measures the sensitivity of an option's price to changes in the risk-free interest rate. While usually the least significant "Greek" for short-term traders, it becomes highly relevant when trading long-term options (LEAPS) or when the central bank makes major policy changes.
A positive Rho for a Call option means that as interest rates rise, the call option price generally rises. Conversely, as interest rates rise, Put option prices generally fall.
Since long-term options (LEAPS) act as a substitute for owning the actual stock, the interest rate represents the "cost of carry." If interest rates increase, the cost to carry a stock position increases, which is reflected in the pricing of these long-dated options.