When planting bedding plants be sure to loosen the soil sufficiently where you are planting them for ease in their ability to root out and establish themselves. Plant at the same depth they were growing in the pot or pack to avoid stem rot disease.
Annuals are heavy feeders. Ideally, mix the recommended amount of dry slow release food thoroughly with the soil where you are going to plant. Mulch to prevent weed growth. Water in thoroughly and then when the plants indicate need thereafter. Enjoy your garden!
-‘Plant Doctor’ Bob