Biological or conventional farming for our olive trees and fertilization, sprinkling, watering, varietie, insemination

Biological or conventional farming for our olive trees?

Biological farming of olive groves provides us olives - olive oil with much more polyphenols. It does not necessarily produce tastier fruits. Dry olive groves produce olive oil of better quality but dry trees do not prosper, which means they do not sprout anymore, making them less productive. The tastier fruits are usually harvested by mountain olive groves (250-400 meters of altitude, as there is less humidity) and calcareous soil (so the soil composition plays a major role but with less productivity). There are other factors as well, such as the microclimate (dry and warm is the best). This explains why Greece produces better olive oil than Spain or Italy. 

Another factor is the weather. During a year, presence or absence of olive fruit bee infestation and the farming procedure. Biological protection from this bee is effective when their population is average to low. In larger populations the best protection is the chemical one. Chemical fertilization produces more fruit but of lesser quality. If the biological fertilization has covered the nutritional needs of the tree and the soil, the chemical one offers nothing more. The best fertiliser is manure and it is used since the ancient times. 

Hydro-fertilization is absorbed faster and probably better for our olive trees. Watering with water that is enriched with manure is particularly nutricious. It is very important to add boron to the soil every three years. Open three holes, 15 cm each, vertical to the tree, insert the boron and cover it. This helps in fruit setting.

Once every four years you should apply copper fungicide paste on the trunks. Ask your agriculturist about the ideal age of the trees eligible for application. Depending on the consistency of the soil, it would be wise to sprinkle your olive grove with lime powder. Marble powder is not advised because it may come from chemically processed marbles.

Single fertilisers are better than complex (because they provide the trees the nutrient they need at the right time), however they are more difficult to be applied and need time - work - extra salaries for workers as they are applied 2 or 3 times. Consult your agriculturist about fertilisation of your olive grove, but i believe that using half or 2/3 of the chemical fertilisation will produce fruit of bigger size. The fertilising elements will probably be absorbed during the second year (at that time the changes to the tree or the darkening of the leaves or new vegetation will be become apparent). 

Even if you performed the best possible fertilisation, if the weather is not ideal the trees will not fructify during blooming). It would be good for our trees to dig holes of 10-15 cm next to the tree, insert hay and cover it with soil. The hay will prevent development of weeds for one to one and a half year. In addition, with its decay it will provide our trees with nitrogen and its roots with warmth. In case the trees have bloomed and there are hot/dry winds together with high temperatures, make sure to water them as much as possible in order to same as many as possible flowers. In general, we do not interact with the trees during blooming.

In the end of April, just before the blooming period, water the trees if it hasn't rained. Just before the inflorescences bloom, when their color change from green to yellow, spray the trees with foliar boron. During summer, it would be advisable  to water the trees two or three times for six hours in order to help the tree acquire new plantation and achieve maximum productivity for the next year compared to not watering them at all.

You should know that the most gourmet-spicy olive oil comes from dry olives. Professional olive oil makers water their edible olives 5 to 6 times during summer for 5 to 6 hours, in order to achieve the best commercial size. Lastly, beware of over-fertilising as it results to less production. If your leaves have dark green color then your soil lacks nothing and it does not need fertilisation. The best way of assessment for nutrients in the soil or olive trees is soil analysis and leaf diagnostics. Olive groves surrounded by carob trees (also found in northern Greece) or have caper plants around them, they have less olive fruit bees. Olive trees rarely flourish next to pine trees. Aromatic plants and pine tree forests do not influence the oil that much as for its aroma. The major factors for quality olive oil are: the fruit that is free from olive fruit bees, its transport to the olive press the very same day and its proper modification to oil. The best biological shield against olive oil bees is to spray the trees with kaolin. However, when the fruits are taken to the press, they must be washed thoroughly in order to avoid traces of kaolin in the olive oil.

Spraying for Chalkidiki variety

2014

February   copper

March        copper + remedy for cycloconium

April           spraying for acarid only if we want the fruit to be edible. If we spray, the oil's quality is not affected.

May             moth + foliar boron, just before blooming when the olive inflorescences change from green to light yellow

June            moth

July             10 or 20. Spraying against olive bee. 10 may be omitted if there is no humidity and no olive bees have appeared

August         olive bee

September   olive bee

September copper

End of September olive bee and duration of pesticide must be calculated so nothing remains on the fruit itself

October        or November after the fruits have been gathered, copper

December     just before Christmas, copper

Consult your agriculturist to define if the copper will be fungicide or hydroxide

During humid days we add a  special glue together with the pesticides in the tank

Spraying during winter must be done when temperature is over 7 degrees Celsius and at 10 or 12 o'clock in the morning, not 8:00.

There is also a second session of spraying for olive acarid, but i don't know when it is performed because i  am interested in olive oil and not the olive fruit. You may ask your agriculturist about it.

Reaming the olive grove or not

Many claim that an olive grove must not be reamed in order to avoid hurting the small roots between the olive trees themselves. No means of farming is cure-all. My personal point of view is that once a year weeds must be destroyed and once every two years the olive grove must be reamed (if the inclination allows it).

This way we do not interfere with the soil all the time but also we do not abandon it either. The pros of reaming are four:

1) The soil is aerated (we break through its solidity

2) The water circulates better when it rains

3) We destroy rodent tunnels (there are rodents that feed on olive trees roots and lead to its destruction)

4) In case of fire in a neighboring farm chances of the fire transfered to our olive grove are diminished.

Weeds must be cut either with a special machine either with a scythe once or twice every year to prevent them from absorbing the nutrients and not cover them.

Soil

The soil of an oil grove is not uniform in its consistency. In some places it may be softer while 5 to 10 meters further it may be not. A more solid cannot be easily improved by man (e.g. to make it softer). Maybe he could soften it up to a depth of 10 to 15 cm by adding manure. This is better for garden plants and less for olive trees, as their roots go a lot deeper.

Olive varieties and fruit setting

I will refer only to three varieties (from Chalkidiki, Megaritiki and Koroneiki) as i know them better from experience and have discussed with other farmers and agriculturists. The variety from Chalkidiki has a more fragile flower than the other two and it needs more ideal conditions to produce a fruit. The Megaritiki produces easier and Koroneiki even more from the other two (but as it is smaller, it is more difficult to collect).

Varieties - olive oil/olive fruit ratio

Koroneiki: 3,5 to 4 kilos of fruit produce approximately 1 kilo of olive oil

Chalkidiki: 5,5 to 7 kilos of fruit produce 1 kilo of olive oil

As far as green olive oil is ocncerned (fruits collected from 15 to 30 of October): 9 to 11 kilos of fruit produce 1 kilo of olive oil

First collection oil (fruits collected in September): we need 15 to 20 kilos of fruit to produce 1 kilo of olive oil.  Its best not collect the fruit if it has rained some days earlier (if we plan to produce oil) because the fruit bloats (higher concentration in water). This means that when separating the oil at the press we will have greater losses in oil, less quantity of oil and at the same time, we have greater costs of production because workers gathering them are paid per kilo collected (about 0,20 Euros per kilo). Moreover we have more costs for transport. 
We don't collect olives when it rains because we increase the risk of carcinoma of the tree.

Fertilisation

If you have plants around your olive grove that block the wind, do not expect the tree to be fertilised because it needs wind for this.

more information here  OLIVE OIL