In hot tropical to sub tropical climate, grow them during winters, in cold temperate climate during spring season.
Well drained, sandy loam soil that is rich in organic matter with 6.5 to 7.0 pH is ideal.
Prepare potting mix with 30% garden soil + 20% cocopeat + 10% sand + 40% organic compost.
In 8 to 12 inches sized pot with 2 or more drainage holes at bottom, fill potting mix and plant dahlia saplings.
Daily 6 to 8 hours of sunlight daily is good for growing Dahlia.
Add water in the pot when the top layer of soil becomes dry. Avoid excess watering!
Add half teaspoon of NPK in the ratio 5:10:10 or 10:20:20 once after every 30 days.
Is Dahlia Perennial?
Dahlia can be perennial, or annuals depending on climate. In USDA zones 8, 9, and 10 they grow as perennial.