Oleanders (Nerium oleander) in full bloom may look like a little slice of heaven tucked into the landscape, but these tender shrubs are deceiving. All parts of the plant are toxic and can cause death if ingested. Grown in containers in northern regions of the United States, or as a perennial in U.S. Department of Agriculture plant hardiness zones 8 through 10, this plant thrives in full sun. When pruned to keep them in shape, oleanders are show-stoppers in the landscape with bright blooms that range from white, pink and red to yellow and coral.
Fill a seed starting tray with moist seed starter. You can purchase seed starter at gardening centers, or make your own from equal parts of peat moss and perlite. Cactus soil mixed with peat moss also makes a suitable soil for starting oleander seeds.
Sprinkle one or two seeds on top of the seed starter in each cell of the seed-starting tray and press them into the soil with your hands. Oleander seeds need light for germination and do not require covering, but aren't harmed by covering lightly.
Mist the newly planted oleander seeds with a spray bottle filled with distilled water. Tap water should be allowed to set for 24 hours to remove chlorine before using it on plants.
Place the seed tray in a warm location that receives bright light or place your oleander seeds under grow lights. Placing the seeds on a heating tape or the top of an appliance that provides gentle bottom heat, such as the top of the water heater, may speed germination. Optimal germination occurs when the soil temperature is 68 degrees Fahrenheit.
Keep the soil moist until seedlings emerge in approximately one month. Some oleander seeds may take up to 90 days to germinate, so patience is the key. Mist the soil whenever it becomes dry to the touch, but avoid soggy soil.