Yes! You can specify your exact preferences by adding a note to any product in your shopping cart. You can state anything from when you want your avocados to be ripe to how large you like your tomatoes. You can do this once you have added an item to your cart in the item panel or in your cart.
You may also add a general note to any delivery order, such as to specify if the driver should use the side entrance of the building. These notes can be added during Step 1 of the Checkout process.