Aloe flowers generally have both negative and positive connotation. The Aloe flowers are associated with affection, along with grief so be careful giving them as a gift.
Camellias themselves have the meaning of love and affection. Red camellias in particular mean the phrase "You're a flame in my heart" so they make for great romantic gifts.
Chrysanthemums are another flower that many people link to love. Red Chrysanthemums in particular are a perfect gift for your significant other as they mean "I love you".
Dahilas have a relatively simple meaning compared to the many other flowers of similar color. Dahilas mean good taste meaning they don't make the most romantic gift.
Red Roses are a common flower to gift the someone's significant other. This is because, like red chrysanthemums, Red Roses mean love or "I love you".
Red is a very romantic color as you have seen from the many flowers before. Red Salvias follow that theme and have the beautiful meaning of "Forever mine".