Elena likes gardens. And flowers.
Kol, in true Mikaelson fashion, looks particularly horrified at the suggestion of taking part in such an unmanly pastime as picking the flowers, but that, in turn, only makes Elena even more determined to have him help her. The disgruntled look he sends her whenever Elena commands him to help her dig the soil and water the roses in her backyard is always worth it, she decides.
("Don't you dare say anything." Kol snarls later. Klaus raises his hands and smirks)