Growing figs from seeds is one step more difficult than most fruit since seeds are not pollinated naturally outside areas with the fig wasp (which are limited to parts of California in the United States). In this post we’ll describe how we hand pollinated, collected, processed, germinated, and grew seedlings from plans in New Jersey.
First we should note that growing any fruit from seeds does not result in plants that produce the same fruit as either of the parents. If the desire is for parthenocarpic, aka common, plants that ripen fruit in areas without the fig wasp, then you need to start with a persistent male fig. Persistent refers to the fact that the fruit ‘persists’, i.e. ripens, even without fig wasps. The gene for persistence is relatively rare in naturalized or wild fig plants, so the chance getting a common female fig from chance crosses is low. The chance is improved (to 25%) by using a persistent male fig for the pollen. The chance of ripening desirable fruit once you have a common female fig is an unknown. Choosing male and female parents with desirable properties (like taste, ripening time, cold hardiness, etc) improves that chance, but it is still relatively low. If you want to grow varieties that are guaranteed to be good, chose clones from cuttings or tissue culture, but fig seedlings offer the chance to create whole new varieties that no one has tried before and is ultimately how the desirable vanities we have today came about.
To hand pollinate figs you first need to grow and fruit a persistent male, or capri, fig. For our first year of this experiment we ripened three fruit on a Saleeb, aka UCR 271-1, tree. This was the first year the tree fruited so only three fruit ripened, but that was enough to pollinate over ten female fruit and grow hundreds of seedlings.
The method of hand pollination came from the ‘Materials and Methods’ section of this paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5126050/ which is also similar to the method covered in this video: https://www.youtube.com/watch?v=XNNtWwaFYCU
Regarding timing, the male capri figs are similar to the breba crop on female fig trees developing the previous season and ripening in early summer (July in New Jersey). When the male figs ripen there are many female figs ready to accept the pollen. In our garden we selected a number of female figs to pollinate. The female figs have to be main crop figs and the larger more mature ones seemed to produce better results than the very immature figs.
The steps for pollinating female figs are as follows.:
1.) After harvesting the fig cut it into halves or quarters to aide in extracting pollen as shown in the picture above.
2.) Tap skin of the fig hard to knock out the pollen onto a clean surface. We used black paper cards so you could see the pollen. Smooth cards would have worked better since some pollen stuck to the paper cards. Pick out the larger bits of flowers from the pollen.
Here is an enlarged picture of the flowers of the Saleeb fig showing the pollen grains before harvesting.
3.) Place the pollen in a vial and refrigerator if you want to save it for later use, or skip this step and mix it directly in the next step. In retrospect we had imperfect pollination of some varieties, so if you have more caprifigs available collect more pollen per batch.
4.) Mix a 2% sucrose solution by combining 2 grams of sucrose per 100 mL (we used 1/2 gram for 25 mL in each batch) of distilled water. We used lab grade sucrose and distilled water since we only got one shot at this per season and both are not expensive, but it is very likely that tap water and baking sugar would give similar results.
5.) Mix the pollen into the 2% sucrose solution. Note that pollen resists water pretty well, so mixing is not easy. With some care enough of it will mix in however. Once your solution is mixed, use 18 gauge syringes (available from Amazon or other retailers) and fill up a number of them before heading out into the garden. We also pre-wrote the date and male fig on the tags so we only had to fill in the female variety in the garden.
6.) Inject the sucrose solution into the female fig until the cavity is filled and a small amount leaks out. The amount varies by fig. The picture below is of a Beltrana fig we pollinated that was very successful (it produced over 100 seedlings), so you can get an idea of the size of fig that worked well.
7.) Finally, label each fig. This summer when we used only one male variety this basically served to show which figs were pollinated so we could harvest them later, but if you are pollinating with multiple varieties the labels are the best way to keep track of the parents of each seedling.
That is it, the figs are now pollinated and you can sit back and wait for nature to take its course.
With the fig pollinated you now wait till they start ripening. In our first year experience it seemed that any figs that ripened before September did not produce many viable seeds. It is possible they needed to be pollinated earlier, or there was another issue with the process, but if figs ripen early and don’t have viable seeds then there is still hope that later ones will produce viable seeds for you.
As the pollinated figs ripen you can start to harvest them. It is important to process one fig at a time and keep seeds from one from mixing with the seeds from another fig or you won’t know the parents of the resulting seedlings. The process we used to go from ripe fig to seeds we could plant was based on the fermentation process used for tomato and other seeds. There are many good articles and videos available on the fermentation process for tomato seeds if you are looking for more information. The process of fermentation helps to separate the viable seeds from the non-viable seeds and other material and helps break down barriers on seeds that prevent early germination. The steps we used were:
1.) Scrape the seeds and other goop out of a single fig into a Mason jar, discarding the skin and any parts not containing seeds. Fill the jar about 1/2 to 3/4 full of tap water, rinsing as many seeds as possible into the jar. Cover the jar with Mason jar lid and a paper towel to keep bugs out, but allow it to breath.
2.) Allow the jar to sit for 3-7 days. We gently shook ours daily to mix the material, but it is probably not necessary.
3.) After 3-7 days the viable seeds should be on the very bottom of the jar. If there are no seeds on the bottom then the pollination was not successful. In order to separate out the goop from the viable seeds decant the mix until only the seeds remain. Do this by pouring off and discarding the goop, adding more clean tap water and waiting for seeds to settle, pouring off top part again, and repeat. Repeat this till the water is mostly clear. Once the water is clear, pour the water and seeds through a strainer.
4.) Allow the seeds to dry for about a day. Placing a paper towel under the strainer can help to wick some of the water away.
5.) Once dry, the seeds can be planted using a very similar technique to annual vegetables. We filled a flat of separable small pots (like you buy vegetable starts in in the spring) mostly fill with rehydrated coco-coir. Sprinkled the seeds over the surface and then added another 1/4 inch of coco coir to cover the seeds. Note that others have reported better luck using vermiculite due to issues with fungal diseases after seedlings emerge. We found that in our low humidity basement (about 45% humidity) that if you uncover the flats when seedlings started to emerge that we avoided most fungal diseases. Results will likely vary by the environment you are growing in.
Don’t forget to label each flat so you remember which parents it came from. If all goes well seedlings will start to emerge after 2 to 4 weeks.
We separated out seedlings as they started to grow leaving one per individual pot. Below is a picture of a flat that is about half separated. The larger plants in the back are ready to be separated and planted in other pots.
After a few a few weeks under lights the seedlings are getting big enough to up pot to 3″ tree pots.
Here are some seedlings from last year, these were chance seedlings from California, that grew outside all summer in 4″ pots. The rate of growth is pretty low the first year compared with cuttings, but it is fun to see all the variability between plants even in their first year.
While this is not a simple process, it is very feasible and results in some healthy new varieties of figs. Time will tell how many are female that ripen figs in New Jersey, and if any of those are great new varieties.