How to Propagate Olive Trees? A Detailed Guide to the Latest Propagation Methods

The olive is native to southern China, growing in mountain gullies at medium altitude. Its flesh is hard and spindle-shaped, and its stone is hard. The olive tree is a commonly used garden tree species, and its fruit can be used in medicine to treat diarrhea. It has excellent economic value. The propagation and seedling-raising techniques for large-scale olive cultivation mainly consist of raising seedlings by sowing seed, combined with grafting. This can preserve the excellent genetic characteristics while also obtaining the quality traits of other varieties. The rest of this article will mainly introduce this seedling-raising method.

I. Raising Seedlings by Sowing

1. Seed Collection

Select high-quality fruit to be kept for seed and leave them unpicked. Wait until the fruit is fully ripe and the flesh has softened, then pick them. After picking, pile them together for about a week to let the flesh rot. Then put them all into salt water to soak and wash, removing the flesh and mucus so the seeds are clean and smooth, then rinse once more in water to wash off the salt water. Scoop them out, let them dry, then store them in sand to complete the after-ripening stage. Use 60% clean river sand, storing one layer of sand and one layer of seeds, piled in about 5 layers. Control the temperature and humidity and check whether they rot or spoil; generally they are stored in sand in a dry, shaded indoor room.

2. Preparation

You can raise seedlings in the ground, but for easier management you can choose containers such as seedling bags or seedling trays. Clean the seedling trays thoroughly and prepare the nutrient soil. The day before sowing, take out the seeds and sort them, soak them in a chemical solution for disinfection, then soak them in warm water for two days. After accelerating germination in an insulated box, sow them, because the seeds are hard and difficult to sprout.

3. Sowing

Sow in early spring, from February to March. After filling the seedling bags with nutrient soil, you can directly place 1 to 2 seeds in each bag. The sowing depth is about 4 cm below the soil surface, with 1 cm of soil covering them. Water and spray gently so as not to wash away the covering soil. Move them to a shaded place or set up a shade net, and spray water once every evening.

4. Seedling Stage

Maintain the moisture and temperature of the soil in the environment. After the seedlings emerge, control pests and diseases. Spread a layer of wood shavings or pine needles on the soil to keep it warm and moist and to prevent some diseases and weeds. After the seedlings emerge, water and fertilize frequently to promote growth.

II. Grafting

1. Timing and Method

Do this before the sap flows, after the seedling rootstock plants have grown and been transplanted, around the end of March, and carry it out on a sunny day when the temperature reaches above 15°C. Take vigorous one- to two-year-old branches from an adult tree as scions, then graft by the cut-grafting method. Work quickly, align the cambium layers, and tie them firmly. Check for survival and re-graft if needed. After they survive, remove the ties and remove the buds below the graft.

Olives can be sown and raised as seedlings and then transferred directly to the field for planting, which preserves the plant's own characteristics. They can also be grafted after raising seedlings, choosing to change and incorporate the characteristics of other plants so they can have multiple traits at the same time. Theoretically, this can be considered two methods of raising seedlings.