Macadamia farming in Kenya has taken shape and farmers especially in central region have taken it seriously.
1. How long does Macadamia trees take to produce nuts?
There are several varieties of Macadamia grown in Kenya. However, a grafted tree will usually start to produce in its 3rd or 4th year after planting. The common varieties include Kiambu 3 & 4, Meru 23 & 24, Taita Taveta 1 & 2, Kirinyaga 15 and Murang’a 20. Depending on your area, you should have reasonable nuts after 7 or 8 years. A seedling tree that is not grafted will usually not produce nuts until it is 7 to 10 years old.
2. What about tree maintenance?
Macadamias are a low maintenance tree and will grow in almost any soil type, as long as it is not water logged. It is a forest tree native to Queensland Australia and likes a good mulch. The main pest in is the green vegetable bug, attacking the young nuts and causing black spots on the nut kernel. Long grass and seeds are known to harbor these bugs, keeping grass short or having it grazed by sheep and poultry will help.
More recently the guava moth has also become a problem pest with pheromone traps and spraying the only solution at the moment. Organic growers and the majority of smaller growers take the risk of loosing some of their crop, in a bad year up to 30% by not spraying. If you decide to spray, then 3 times a season will do the job, starting 3 weeks after flowering at intervals of about 3 weeks.
3. Can macadamias be pruned?
Yes, but be aware there are 2 types of trees, Droppers and stickers and pruning varies for each type.
Macadamias will stand quite heavy pruning. The aim when pruning is to keep the tree to a manageable height (3 to 4 meters). Do this by cutting strong leaders out of a sticker type tree or pruning the outside of a dropper variety. This will open up the interior of the tree to light, air and bees to help with pollination, particularly because Macadamias tend to flower into the center of the tree.
In short, keep the tree low and open on the inside to aid pollination and to make picking easier. Reduce multiple forks to a maximum of two to avoid the incidence of wind damage.
4. When are macadamia in Kenya ready for picking?
For varieties which do not drop their nuts, the simplest way is to look at the lining of the husk after the shortest day of the year. When the lining has turned deep brown, to about the same color as the nut inside, the crop is ready for picking. Depending on the weather and position of the trees this can be as late as April. Beware, trees can drop (abort) quite a lot of nuts if stressed by drought, these nuts will be immature and can be mistaken as ripe.
5. What to do after picking
Below are a few things you should do after picking. However, in Kenya most companies will buy the nuts while still at the tree and they will carry them to the processing plant.
- Remove the husks preferably within 24 to 48 hours of picking.
- Bag the fresh nuts in 10kg onion sacks and hang them in an airy and shaded position (open carport is ideal), for a 3 month minimum. Hang them out of the reach of rats and mice who love chewing through them. During drying the nuts will loose about 15% of their weight.
Larger or Commercial growers will tend have a drying room with heat up to 350C lots of air movement and dehumidifiers operating.
- Once dry, store them on or near the hot water cylinder for a minimum of 3 weeks. The additional weight loss after this drying will be approximately 10% (a dehumidifier can be very helpful).
Larger growers will have dried them to below 3% moisture in their drying rooms ready for cracking as required.
- Once fully dry and ready for cracking (less then 3% moisture) . The kernel will ideally be rattling in the shell and above all, will be crunchy and sweet.
The above process is meant for those who plant macadamia for own consumption. However, commercial macadamia farmers who intend to make money sell their nuts to companies such as Jungle nuts, Sasini, Kakuzi etc..
6. Do macadamias nuts last long?
All nuts deteriorate over time, however macadamias ‘in shell’ will last for a couple of years in a dark, cool and airy place. After cracking, the kernels will last for about six months if kept in an airtight and moisture proof container. Larger growers with vacuum seal kernels or Nitrogen purge and pressure seal bags to keep the kernels fresh for a considerable time.
If you have any other questions about macadamia growing please contact us and we will do our best to help you.