It comes down to the soil. Good quality, well draining, organic compost rich soil will be your best friend when it comes to growing petunias and verbena together. Use the compost rich soil to give the plants the boost they need to get established, then follow up with a water soluble fertilizer once a week or so to keep the vigorous growth green and lush. Full sun with some afternoon shade will assist the plants with the energy they need to provide the myriads of blooms all season long. Both plants will benefit from a regular watering routine, wait until the top two inches of the soil is dry to prevent overwatering and prevent root rot.
 
All flowers are subject to availability.  Substitutions may be necessary.
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