GROWING HIBISCUS IN THE GROUND
If you live in an area where you DO NOT experience frosts and your temperatures are always above freezing, your hibiscus can happily be planted in the ground. (If your temperatures dip into the 30s or below then these wonderful plants should be grown in pots and moved inside until all danger of frost has passed.)
In addition to normally mild weather, there are a few more requirements for in-ground planting. Before planting, dig a hole twice the size of the pot, fill it with water, and see if the water sits or drains. If it does not drain well, dig the hole deeper and wider. You will now have a pile of dirt. Add perlite or black lava cinders and matured compost to the soil and mix it in. Return the soil to the hole - you have just created drainage! Hibiscus love water but must have good drainage.
Although tropical hibiscus need sunlight and warmth for best growth, too much sun or extended very hot weather can harm them. If your weather often gets above 90 degrees during the summer, your hibiscus can become “sunburned” or dehydrated. The flowers can bloom in strange forms or unusual colors and/or your plant can die. If this is the case in your area, consider planting in an area where there is filtered sun or partial shade during part of the day.