Much has been written about growing palm trees from seed and one can find a lot ofvarying advice on the Internet concerning this subject. The following is the result of reading much of that information, followed by trial and error (lots of error it must be said) in order to give you the best advice I can. It should be noted that growing palms from seed is very easy, but easy does not always equate to quickly. This is an important distinction. Once treated and sown, the need little more than your patience.
1. First priority, the seed must be fresh – I only sell fresh seed, I know it to be fresh because I have either collected it myself or it has been collected for me. A note here is needed on the definition of fresh. Fresh may mean straight out of the fruit and dealing with in few weeks - such seeds are few and far between in commerce because of short shelf lives. The seeds we deal with have a minimum shelf life (fresh) of 39 weeks and a maximum (in some cases) of a few years (normally larger, harder seeds).
2. When you receive the seed, clean it of all flesh, as leaving this on will delay germination and may lead to rot. Of course some will not have any flesh on them and these can be taken straight to stage 3.
3. Having cleaned the seed, soak it in tepid water for 2 – 5 days, the larger/dryer the seed, the longer the soaking period. Change the water daily or more if it is discoloured.
4. At the last change of water add a copper based fungicide at the recommended strength for seedlings or use Chinosol. (I have used both with equally good results). Good results are also reported for diluted Neem oil. Many of the decent fungicides have now been withdrawn due to health concerns with the amateur grower. You can always soak in dilute bleach for the final few minutes, provides you rinse all traces off at the end.
5. For the sowing medium I use Vermiculite. This should be dampened and I mean dampened (approx 30 – 50 ml (boiling) of water per litre of vermiculite). Place the seed and (cooled off) vermiculite in a Ziplock bag, seal and place somewhere warm and dark, I use the airing cupboard (my wife complains bitterly – so I usually hide the bag somewhere out of reach).
6. Leave it all alone for at least week, then regularly check (every week) for signs of germination. Don't open the bag unless you see positive signs of germination, either a root or a shoot from a seed. Patience is the key, some seeds will germinate in a week or so, most take 12 weeks or more and some can take over a year or more. The point here is not to write things off, eventually they will germinate and they are in the best conditions for them to do so. Bigger seeds usually take far longer to germinate than smaller seeds. Bismarckia, for example, may take 18 months for the root to appear. The importance of being patient cannot be overstated.
7. As the seeds germinate, remove them to a gritty, moist peat mix compost in a standard pot. Here I put 10 up to seedlings in a 9cm square pot. Give a light spray and seal in a polythene bag and place somewhere bright but out of direct sunlight. The bag keeps in the moisture without the need for extremes of watering, both of which are fatal for palms – trust me I’ve done it.
8. The plants can stay in the bag for months, just keep a check to ensure that the compost doesn’t dry out, the leaves don’t start to overfill the bag or the roots come out of the pot.
9. Once the plants are growing well and this could be 6 – 12 months, pot them individually into a suitable pot size.
Best of luck, remember though at all stages hygiene is the key, once a mould gets hold of your seeds you may as well start over – again I’ve been there.