and Lavender are not usually recommended as companion plants due to their opposing needs.
Lavender likes sandy, lean soil and does not need large amounts of moisture or excessive amounts of fertilizer. Lavender can handle some drought after it is established. roses
need well enriched loam soil, lots of watering and are heavy feeders. Consistent moisture is probably the number one requirement of roses
Moist soil for roses
means bad news for the roots of lavender which are prone to root rot and fungus if they constantly sit in wet soil.
Can you plant these two fragrant beauties in beds across from each other rather than in the same bed? Like on both sides of a path? That way you get the look, fragrance and healthy plants.