Olives are a common commercial crop and are often grown in their gardens. Although olive trees, like many other plants, live for thousands of years, certain conditions need to be created for them to be grown. How to grow olives from seedlings to mature plants? How to use various techniques like experienced farmers to make olive trees bear delicious fruit? This article will reveal them all for you.
Choose Growing Place
- The first thing to do is to determine whether the climate where you live is suitable for growing olives. Generally speaking, crops are suitable for growing in such a climate: warm winters, hot, dry summers and long periods of time. Areas suitable for growing olives include the Mediterranean region of Europe and the coastal valleys of California. In the tropics, it is difficult to grow olives.
- Olives have a hard time surviving frost without protection. When the temperature drops below minus 5 degrees Celsius, the small branches of the olive tree will start to suffer, and below minus 9 degrees, the larger branches and even the whole tree will suffer. Also, even if a frosted olive tree survives, the fruit and the oil it produces will be much less flavorful.
- However, olive trees also need cooler days to grow. When the olive tree blooms, the temperature must be below 7 degrees, but this temperature is not absolute, and it depends on the variety of the olive tree. This is why growing olives in the tropics is so difficult.
- Make sure the climate is mild and dry during the flowering period. The optimum climate for the olive bloom period (April to June) should be dry and mild, with no overheating. Olives are wind-pollinated, so excessively wet weather can prevent olive trees from bearing fruit.
- Planting areas should have good drainage. Poor drainage is one of the most common causes of death for olive trees. When looking for suitable planting sites, be sure to avoid those with poor water flow. Olives don’t like to get wet, and a great way to solve drainage problems is to plant them on gentler slopes.
- Do not choose very fertile land. Especially fertile soil is a bit too much for olive trees, but in fact, olives grown in more fertile soil taste the best.
- Optimal planting conditions include fine soil (eg loam), well-drained, and well-ventilated roots. You can also grow olives in soft soils such as sandy soil.
- If the soil is deficient in nutrients, 18-45 kg of nitrogen fertilizer can be applied per acre (about 4 square meters per acre) per year. In addition, you can plant some fertile crops such as beans next to the olives; or apply some compost.
- Pay attention to the pH of the soil. The soil should preferably be slightly acidic or neutral, and the pH should be between 5-8.5, with many farmers agreeing that 6.5 is optimal.
- The first thing to do is to decide whether you want to grow olives for pressing or table olives, or whether you want to produce both oil and eat. While all olive varieties can be used for oil extraction, some, such as Izmir Sofralik, are used exclusively for oil extraction, while others, such as Mission olives, are mainly used for oil extraction. for consumption. The olives that are grown for consumption should be watered frequently, and the olives that are grown for oil extraction should be watered less.
- The second thing to know is whether the variety you choose is self-pollinating. Self-pollination means that the olive plant does not need plants of other varieties to pollinate it. Plants that are self-sterile require pollination from nearby plants.
- Arbequina is a self-pollinating plant, which means it does not need another plant to pollinate it. The Albertina olives produce fruit the size of a grape, and the clusters are very dense. The olive oil of this variety is of high quality, but does not last long.
- Arbosana olives are self-flowering sterile plants. This olive needs to be planted with any of the following varieties of olives to produce fruit: Maurino, Coratina, Pendolino, Frantoio , Leccino and Olivastra.
- Plant olives in pots. Smaller plants are more suitable for planting in grow bags. If you decide to plant in a pot, pick a larger one, at least 60cm deep and 60cm wide.
- Make sure the drainage is clear. Remember, wet soil is the natural enemy of olives. The selected soil can be sandy or loamy, with moderate irrigation. Wait until the soil has dried to at least 25cm below the position before watering.
- Potted olives require more care and require more pruning than olives grown in the ground. Potted olives require frequent pruning, and many farmers agree that olives should not have too many branches, generally just three or four main branches.
- If you decide to plant in the ground, sprinkle 70-85 liters of nitrogen fertilizer or well-composted animal manure on each planting site. Each fertilization area is about 22 cm * 22 cm, and if the area is too large, there is a danger of repeated fertilization.
- Sprinkle lime to increase soil pH. If the pH of the soil is below 6.5, then you can add a little lime to increase the alkalinity of the soil. If you want to accurately measure pH so that the pH levels are equal everywhere in the soil, contact your local agriculture department or fertilizer dealer.
- Loosen the soil in a 3-meter wide area next to each row of plants to a depth of at least 0.6 meters. Loose soil aids in drainage and ventilation, which can promote olive growth.
- The loosening process also mixes fertilizers, lime and other trace minerals in the soil. Fertilizer and lime build up on the surface won’t work, so it’s best to loosen the soil and turn it under the soil.
- After loosening the soil, you can use a grader or rotary hoe to level the soil, although this step can be omitted.
- Transplant the potted olives to a sunny place outdoors, paying attention to the height of the ground and the height of the pots. Transplanting is best in April and May, as there are few frosts in this season.
- Dig a hole about the size of the opening in the pot.
- Remove the olive plant from the pot and inspect the roots. Cut off any tangled roots, but be careful not to damage the bulbs
- Plant the plant in the hole and fill the hole with the soil you just dug and the surrounding soil.
- Water and cover with straw. Mulching with straw has the following benefits: straw retains moisture, keeps the soil cool and prevents weeds from growing. The straw should be bought in bundles that have been rained on, which is cheap and has good mulching effect.
- In addition to straw, mulch also includes: stems and leaves of alfalfa, soybeans, peas, etc. These plants are high in nitrogen and rich in many nutrients needed by olives.
- When covering straw, do not cover it within a radius of 10-15 cm from the root of the plant, so that the root system has enough space for ventilation.
Cultivate to Maturity
- Water less. In California, a brisk watering once a month is generally enough. Prolonged immersion of roots in water can damage plants and affect the taste of the fruit.
- Remember, the amount of water you use also depends on whether you use it for food or oil. If it is edible, it is necessary to water more, once a week or once every two or three weeks. If it is used for oil extraction, it is necessary to water less, so that the oil extracted will have a stronger taste.
- Learn the correct method of cutting with a pruning shear. Late winter and early flowering are a good time to prune. While not all olive varieties require pruning, scientific pruning can help the plant grow in balance and produce delicious fruit. Trimming off excess branches and fine roots can control the height of the olive tree to facilitate fruit picking, while also ensuring that the fruit is evenly set.
When pruning, keep the following points in mind:
- “Less is more”, don’t prune for the sake of pruning.
- Young seedlings do not need to be pruned as often as mature ones.
- Pruning should be from top to bottom.
- Trim the big branches first, then the small ones.
- Pruning is not only for aesthetics, but also for the healthy growth of the olive tree.
- The branches that can not be cut this year should be kept for next year.
- Understand the conditions of the results. Olive trees planted this year will not bear fruit until next year. Olive fruit will only bear on the branches that grew up the previous year. If you cut off too many new branches, the olive tree may not bear fruit.
- Beware of pests and diseases. Like most plants, olive trees are subject to pests and diseases, especially the black scale insect and the sclerotinia. As a grower, you need to spray pesticides to prevent pests, but also pay attention to using pesticides in moderation to ensure the natural purity of olives.
- Black scale insects, as their name suggests, are small and have a black shell. Black scale insects are native to Africa and can lay more than 2,000 eggs at a time. Although black scale insects tend to invade already weakened olive trees, healthy olive trees can also be infected. As soon as black scale insects are found on olives, be sure to spray them with a suitable insecticide.
- Olives may also get verticillium wilt, causing leaves to fall off and branches to shrink. Although some varieties of olives are immune, there is currently no cure for the fungal disease Verticillium wilt. Once there is a shrinkage of the branches, be sure to prune them immediately, otherwise the shrinkage will spread to other parts. If you find that olives on a field have verticillium wilt, stop planting olives on that field.
- You know, olives take years to bear after they are planted. Well-watered olive trees will bear fruit within two to three years, while olive trees that have been less watered will bear fruit more slowly. While some varieties of olives will generally bear fruit within two or three years if properly cared for, there are many varieties that take 10 years to bear fruit, and even 20-30 years with less irrigation.
- Pinch accurate harvest time. The olive fruit is green at first and turns black as it matures. Olives picked when they are still green have a pungent and astringent taste, more like herbs, while olives picked after they have darkened in color have a milder and softer taste. Many olive oils are pressed from near-ripe olives, that is, olives that are between cyan and black in color.
- Ripe olives are easily crushed, so take extra care when picking them.
- Olive trees in California are susceptible to Verticillium wilt. To prevent Verticillium wilt, it is necessary to prune dry branches in time to avoid planting olive trees in soil infected with Verticillium wilt.
- Olives in the Mediterranean are vulnerable to the Mediterranean fruit fly and the olive fruit fly.
- Make sure your pruning tools are hygienic, and try to prune in the rainy season. Pruning tools may carry olive knotweed, which can be transmitted to other plants through pruning tools.
- Do not give auxin to olives used for oil extraction, otherwise the oil will have a chemical smell.