Planting is the fun part! Starting in March, you can begin planting carrots, chives, parsley, and spinach seeds outside. This is also a good month to add compost, if you’re using it. Come April, you’ll be ready to plant beans, cucumber, tomatoes, and ornamental grasses. Sweet potatoes and annual flowers should be planted after the last freeze. For all your beautiful ornamental flowers, such as marigolds, petunias, daisies and dahlias, May is the perfect month to plant.