“The ease with which old garden pinks escape and multiply in the wild is proof of their tough constitution.”
Carnations are easy to grow if you have the right climate. They like a lot of sun, and they do not like cool foggy weather. In San Francisco they will develop mold and fungus type of rots and die. The like rich soil as long as that soil is well-drained. The do not like clay soil. Create a soil made with sand and healthy compost, as well as some bagged soil mixes. Allow the soil to dry out between waterings. They do not like humidity in the air. The dry summers of Northern California are ideal conditions for carnations. They may even do well, in the dry air of the desert, but one would need to remove the desert soil and replace with normal garden soil or a healthy soil mix. The can be divided every three years, just like some hostas. They may do better after division.
February 18, 2019 We have had a lot of rain in northern California, but my big pink Carnation is still going strong. Apparently it is able to handle excess water due to the soil improvements I have made. The Carnation seems to almost double in size yearly. I have not divided it yet. However, in the summer I may have been over watering it, due to the heat. It is not that good to over water in the extreme heat, but yet if you don’t over water the plant could die. Watering reduces the plants soil temperature, and is cooling, but when over watered the roots have trouble with beginning to rot. Rotten roots interfere with the plants ability to uptake nutrients from the soil. An over watered plant may look just like an under watered plant, so often people panic and water even more which brings the plant to an unhealthy state and perhaps death.
My smaller hot pink carnation is also looking very well right now. I don’t remember this one as blooming pink. I recall it blooms purple, but this photo makes it look hot pink. Here is how it should look at peak bloom in spring before the summer heat sets in.