Broccoli flowers attract a lot of bees! Of course you have to let some of your delicious edible florets develop into flowers instead of harvesting and eating. But they are total bee magnets.
If you have a lemon tree, you are probably in FL or CA? Now is a great time to plant broccoli, and plant enough that you can let a plant or two go to flower, and still have enough to harvest and eat. I plant out transplants at this time of year and also plant seeds of other varieties for an ongoing harvest. My Earth Box holds 4 plants, and I let one go to flower while eating from the other three.