How to Germinate Orange Seeds

Orange Seed Germination

Seed

Collected seeds are washed by placing them in a bowl of water and swishing them around to loosen any attached orange pulp. Seeds that float and seeds that are small in comparison are not good for germinating. Remaining seeds are cleaned, folded into a dry paper towel and placed inside a sealable plastic bag. To break seed dormancy, seeds are refrigerated for three to four weeks; seeds collected from store-bought fruit have already had a refrigeration period, so refrigeration is no longer necessary.

Soil

Orange trees prefer neutral to slightly acidic soil and the best germination medium is soil-based. Garden soil is sterilized through covering and heating to 180 degrees in a home oven for half an hour. Commercially bagged topsoil has added amendments to increase moisture retention, friability and drainage. Sphagnum peat moss and vermiculite or sand used in equal parts with soil makes an appropriate germinating blend. When peat moss is used, it is important to place the soil in pots and to water several times to ensure the peat moss is moistened.

Planting

Before planting, orange tree seeds are soaked in water for at least two hours, or overnight, to hasten germination. One seed is planted in a 3-inch pot, or several seeds evenly spaced in a large pot, to a depth of 1 inch. The pot is watered and allowed to drain before placing it in a warm, sunny window or on a seed propagation mat with the thermostat turned to 61 degrees Fahrenheit. In the spring time, when outdoor soil temperatures are warm enough, seeds can be sown directly in the ground.

Germination

Germination times can take as long as six to eight weeks or more. Meanwhile, the soil is not allowed to dry out, but not waterlogged either, as too much moisture will cause the seed to rot. After the first true leaves emerge, the seedling orange trees benefit from daily misting with water. To speed up germination, a gibberellic acid soak is used. A plant hormone, gibberellic acid can be purchased from some garden supply stores or online.