While roasted broccoli won't spoil in the fridge, it won't stay good for more than 2-3 days. Make sure you store the roasted broccoli in an airtight container. Broccoli loses its flavor after a few days. If you plan to keep leftovers of roasted broccoli, I would suggest keeping some of the lemon and garlic sauce and drizzling it over after you reheat the broccoli.