This shows off the sprouts and entices gardeners to buy. Farmers often remove the lower leaves to speed up harvesting. I recommend you leave the leaves intact. They produce the energy for the plant. The more energy produced, the bigger the sprouts.
Sprouts are ready to harvest when they are firm and one inch in diameter.
Their quality and flavor is best when the sprouts develop during cool weather. Don't worry if you accidentally remove some leaves during harvest. Personal replies are not possible but matters of general interest will be answered in the column. I have two dwarf Alberta spruce growing in large plastic pots. You need to provide insulation for the root system.