Altitude range

Avocado will thrive well at 200 to 1000 masl

Soil type and conditions

Deep soil, with good water holding capacity and free draining.It requires a pH: 5.5 – 6.5

Avocado nutrient requirements include; N, P, K, Mg, Ca, Na, B, S, Zn, Mn, Fe, Cu, Al, Mo

Temperature range

The temperatures should be 16 – 24 ^oC.  Above 33^oc fruits suffer heat damage, below 4^oc impaired growth of tree

Rainfall

Rainfall of 600 mm is essential during production period

Steps during land preparation

1. Clear the field of trees, bushes and weeds
2. Prepare only planting holes
3. Prepare, in advance, planting holes 60cm x 60cm x 60cm  
4. Separate topsoil and sub soil
5. Spacing may range from 6m x 6m, 6m x 7m or 8m x 10m between trees depending on growth characteristic of the individual variety and the type of soil

Nursery site selection

Ensure; nearness to quality water source, good drainage, security from animals, thieves etc, and accessibility to the road and availability of wind breaks e.g. Casuarina, Grevillea etc

Nursery establishment

Prepare a seedbed of width 1 m and a desirable length by removing farm soil from the seedbed to a depth of 30 cm and refill the 30 cm depression with sand

Seed preparation

Collect seed only from healthy and vigorous mother trees and from fruits which are mature and healthy rather than from off the ground

Large sized seeds generally produces vigorous seedlings

Cultivars used as rootstocks are Puebla or Local varieties, Fuerte is not resistant to Phytophthora

Extracted seeds should be treated in hot water not exceeding 50 ºC for 30 minutes

Coat or dipped in a broad spectrum fungicide e.g. Metalaxyl to prevent infection with Phytophthora cinnamoni

Sowing seeds

Plant seeds with the flat basal end  pointing downwards either in nursery beds or directly into eco-bags, about 20 cm in diameter and 30 cm deep

Transplanting

About 20 days after germination, plant should be 20 cm high and having developed two pairs of leaves

Transplant open seeded seedlings in nursery beds by uprooting and planting into containers

Potting media should be medium texture, sterilized if possible and with good drainage properties

Grafting

The rootstocks are ready for grafting 6 months after transplanting into biodegradable containers 6 X 9 inches

The rootstocks are grafted using scions of desired variety

4 to 6 months later, the seedlings are ready for transplanting into the field and should be well healed and free from pests and diseased

Hass and Fuerte are the most preferred by the consumers

Orchard establishment

Water the hole just before planting to ensure contact of the roots with moist soil

Remove the eco-bag and hold the soil media around the roots

Maintain the position of the level of soil as it was in the eco-bag while planting and firm the soil around the planted seedling

Water well and mulch after transplanting 

Water young plants frequently for proper establishment

Do hand watering 2 to 3 times per week for planted seedlings for four weeks

Irrigate grown up trees at 10-15 days interval from fruit set to maturity

Irrigation can also be applied to stimulate flowering after a distinct dry spell

Explore drip irrigation bottle in dry regions

Irrigation is not recommended for 2 – 3 months prior to flowering as it is likely to promote vegetative growth at the expense of flowering

There should be a marked season with dry weather for flowering and fruiting

Keep the orchard weed free in the early stages of growth

In mature trees, weed 2 m strip along the rows and cut grass in the rest of the field

Mix one debe (20 kg) of well decomposed manure and 125 g of DAP with topsoil and return the soil to the hole dug earlier to refill the hole

In the early years, avocado require high levels of nitrogen but after they begin to bear, the fertilizer should be higher in phosphate and potash

Apply 1 debe 20 -30kg of well-decomposed manure annually: The quantity of manure applied increases with age of the crop; 4 debes each year at an optimum production from 7^th year

Spread fertilizer or manure around the drip line of tree canopy and mix with the soil. Applied in a ring at the beginning of rains

Under dry conditions, the hole should be bigger about 90 x 90 cm and 100 cm deep

For irrigated orchard apply the same quantity of manure  any time of the year  but this should be followed by increased application of irrigation

For Top dressing fertilizer use 120-130 g of  CAN or 50-60 g of Urea per stoo

Pruning

Pruning is done at an early stages before the plant starts to flower

Pruning may also be done after harvesting the internal dormant stage of crop development

Pruning

Common pests of avocado include;

• Red spider mites
• Avocado thrips
• White flies
• Fruit fly
• Fruit bug

Major diseases include;

• Scab
• Cercospora fruit spot
• Anthracnose

• Scales

Scab -  infonet-biovision.org

Cercospora fruit spot -  infonet-biovision.org

Anthracnose -  infonet-biovision.org

Avocado root rot

Caused by poorly drained soils and flood prone areas

Anthracnose

Mostly attacks mature seeds forming dry ,dark spots

Control

Prune dead branches and twigs

Spray with appropriate fungicides e.g. dithiocarbamates, at interval of 7-10 days depending on weather conditions

Spray copper-based fungicides e.g. Nordox or copper oxychloride.  Repeat every 14 days

Curative chemical e.g Topsin

Roots of other tree bushes harbour fungal pathogens that affect avocado roots

Powdery Mildew

The fungus attacks all forms of young tissues of most importance to growers are fruit panicles and young fruits. In severe attacks, the entire blossom panicle may be infected, and the fruits fail to set

Control

Foliar sprays with protective and curative fungicides as appropriate

Spraying should start at 20 % blossom then continue at about 3 weeks interva

Maturity indices include; Change in colour from green to black or purple in dark varieties

Fruit stems turn yellow  and the fruit skin may sometimes turn  lessy shinny

The end of the green varieties  may develop rust-like  spot

Fruits float on the surface when immersed into water

Harvesting

Avocado starts bearing within 3 years after transplanting. Peak harvest occurs between March – September in Kenya

Avocado is picked and stored at room temperature for 7- 10 days. If they soften without shrivelling, then the fruits is ready for harvesting

Fruit should be pulled from the stalk but cut off leaving a 3 cm stalk

The yield increases as the tree continues to grow.

250-300 kgs per tree per year (8-10 tonnes/acre)

Cartons should be well ventilated and should have a handle for handling

Fruit should not rub against each other during transportation

Pack the fruits in single layer in fibre board cartons, to void rubbing against each other that can shorten the shelf life of the fruits

Transport or store mango at 11^oC for green fruit and 8^oC for riper ones

Most varieties can store at temperatures between 10^oC and 13^oC with relative humidity of 85 to 90% for a storage period of between two to four months

Store the produce in a cool dry place. This will minimize internal chemical reaction that may accelerate early ripen before they reach the market

Pre-harvest practices influence the post-harvest procedures e.g. size, colour

Store the field boxes in the shade in order to minimize sunburn, loss of moisture and dust

accumulation Value addition techniques include; sorting, Cleaning, pre-cooling and grading Sorting: Remove all the field debris including

misshaped, diseased and bruised fruit

Cleaning: Use cold, clean water to remove any dirt found on the fruits

Pre-cooling: Fruits must be cooled as quickly as possible Fuerte and Hass must be

cooled to 5^oC – 7^oC within five hours of harvesting

Grading: Fruits are graded according to size and stage of ripening

Ensure fruits for export market are graded by the set size grades/code

Processing

Generally, Avocado is served raw (ripe), though it can be processed into juices, shakes, ice creams, dips, pastes and purees