My dieffenbachia &Alocasia are planted in my garden
How do I keep it alive outdoors?
This is going to prove very difficult. These plants can start to suffer even as the soil temperatures approach the 50's. You will want to dig them up very carefully and bring them indoors, OR put up an inexpensive greenhouse around them. Both of these plants are distant relatives of each other, and require very similar care. The more sensitive one being the alocasia. Have a great deal of caution when handling these plants, as the inside contains calcium oxalate at high levels, which can irritate the skin, and throat very badly. Here is a link that will help you care for these plants: https://www.gardeningknowhow.com/houseplants/alocasia-plant/growing-african-mask-plant.htm