COMPANION PLANTING.
To help keep the risk of disease to a minimum it's a good idea to consider companion planting. Garlic is an ideal consideration as are onions, marigolds, mignonettes and thyme. Many organic gardeners companion plant and as a result do not have any problems with pests. This is because the pheromones (odours) given off by the companion plant deters insects and act like a natural insect repellent.
DEADHEADING.
Once a bloom is all but spent then it's a good idea to remove it. This is called deadheading. The plant will respond by putting more energy into one that is developing.