On flowers, fruits, birds, bees, palaces
and the fascinating story of the fig tree
It’s been a while since I had a moment to write. I have been busy teaching and tending to and enjoying my land here at La Source.
Wandering through my garden, I have been enjoying its flowers and pondering which will produce fruits or vegetables which I can eat, like my potatoes or fruit trees, and which are simply there to give beautiful flowers. And will the CD’s I see fluttering in the wind which I carefully tied to the cherry trees, stop the birds eating all my cherries?
Then I realised that my fig trees don’t produce flowers and that not all the flowers in my courgettes and melons produce fruit. I never quite understood why the nursery told me to buy 2 different varieties of each fruit species, although I was able to buy only one kiwi plant because it is “self-fertile”. It made me start to think more about reproduction in plants and how it compares to human reproduction, especially since I sometimes use images of flowers to connect with my reproductive organs. How like flowering plants are we? Traditional Chinese medicine views us as a microcosm of the world around us.
How do plants reproduce?
Not all plants reproduce through their flowers, although around 85 – 90% do. Some, like mosses and ferns, reproduce through spores, and others, like pines and cypresses reproduce through male and female cones. Some plants can reproduce asexually, which means that they do not fuse their male and female parts. This is through processes like budding, or modifications of their stems or roots, but I won’t go into that here. When a plant reproduces sexually its flowers contain their reproductive organs, so a flower can be a a good image to connect with our own reproductive organs, which I like to call our “Palaces”.
The birds and the bees
We all know that it is through birds, bees and other insects as well as butterflies, birds, reptiles and the wind, that pollen is moved around flowers. I pondered more on where pollen comes from and what happens to it. Pollen contains the “sperm” and is moved from the male part of a flower, the anther, to the female ovaries where it fertilises (pollinates) the ovules (“eggs”) so they can grow and form seeds. I hadn’t realised that this can happen on the same plant as well as on different plants nor that some plants don’t necessarily need the birds and bees because they can fertilise themselves.
The fertilized “embryo” in the ovary of a flower develops into a seed and the surrounding tissue often develops into what we know as a fruit. The seed enables the plant to reproduce, but it can provide us with delicious food, like sunflower seeds and walnuts.
Not all flowers are the same - some are “perfect” and others are “imperfect”
“Perfect” or “Complete” or “Hermaphrodite” flowers
Some flowers are “complete” ,“perfect” or “hermaphrodite” . This means that they have male and female parts within them. The flower also has outer parts - the petals which are often colourful in order to attract pollinating animals and the sepals which are protective, leaf-like structures.
The male parts are the stamen - the filament and anther. The anther produces the pollen which contains the male reproductive cells, like the sperm.
The female parts are the pistil -stigma, style and ovary. The stigma attracts the pollen, like the vagina attracts sperm, and is often fuzzy. As the pollen germinates it forms a pollen tube which goes down the style to reach the ovary which contains ovules, the flowers’ “eggs”.
Although a complete flower can pollinate itself (self-pollinate) or another flower on the same plant, this is not as good as being pollinated by another flower of a different plant of the same species. It’s like with humans - if we reproduce within our family, we get “inbreeding” and lack of genetic diversity. This is why even though many fruit trees are self-pollinating, they crop better when another variety of the same fruit species is planted nearby. If bad weather deters pollinating insects or temperatures are too cold, the pollination may be poor and there will be a reduced ""fruit set"". Now I know why I had to plant 2 different varieties of the same species. They’ll also give me a choice of cherries too - as long as the birds don’t eat them all.
The majority of our native plants and crops form hermaphroditic flowers:
Apple trees (Malus spec.)
Pear trees (Pyrus spec.)
Cherry trees (Prunus spec.)
Roses (Rosa)
Olive trees (Olea europaea)
Most vegetable plants: many beans, aubergines, eggplants, lettuce, okra, peas, peppers, strawberries and tomatoes.
Many ornamental plants, for example daisies (Bellis perennis)
“Imperfect”, “incomplete”, “unisexual” , “male” or “female” flowers
These flowers don’t have both female and male parts. They either have the male or female parts. These male or female flowers can be on the same plant. These are known as "monoecious" plants : literally meaning "one house". However, these flowers can be on different plants of the same species. These plants are “dioecious”. They have two houses - male plants (with only male flowers) and female plants (with only female flowers). Only about 5% of plants are dioecious. Holly and asparagus are among them. Some plants have been bred from dioecious plants to make monoecious plants like kiwis and grapes. Now I know why I could choose to buy only one “kiwi” but am wondering now whether I should have bought a male and female kiwi plant as well to compare the fruits!
Some examples of monoecious plants are walnut and sweet chestnut trees, maize and the cucurbit family, which includes cucumbers, courgettes and melons. In these plants the male flowers are smaller and more numerous than female flowers. They flower earlier in the season than the females and it is the female flowers which set the fruit. If you want to eat fried courgette flowers, which I love, make sure you pick the male flowers if you want fruit.
Not all flowers produce the part we eat!
The pretty purple flowers of potatoes may make us forget that they are a member of the deadly night-shade family (Solanales). This family includes aubergines, peppers, and tomatoes. Some members are monoecious or dioecious. They can also be andromonoecious - male and hermaphrodite flowers on the same plant!
Their flowers are poisonous to eat. They won’t kill you, but you won’t feel that great. The flowers are a sign that the potato is nearing the end of life because they are attracting pollinators so that the plant can reproduce. If you want large potatoes, then you need to cut the flowers off so that its energy can continue growing the potatoes, rather than making seeds. I’ve recently discovered that it’s the same for onions too. I didn’t break off the flowers and the stems early enough, so my onions are small.
The fascinating story of the fig wasps - do we eat them when we eat a fig?
Did you know that each fig is hundreds of inverted flowers? They are flowering but we don’t see them because their petals are on the inside. These means that they can’t count on the normal ways of insects or animals or wind spreading their pollen. They are pollinated by female fig wasps which lay their eggs inside them. I love this story of co-evolution between figs and wasps.
Fig trees are said to be one of the most essential plants on earth. They are very resilient and can thrive in both flood and drought prone conditions. They are considered a keystone plant because most fruit-eating species depend on them. As many as 1,300 bird and mammal species like to eat them, and many go on to disperse their seeds. This means they can help replenish barren environments.
755 species of fig have so far been identified and an estimated 1300–2600 fig wasp species are in existence. Fig trees began as monoecious species, but some have evolved into dioecious. This helps to stop their seeds from being over-exploited. Most fig trees are pollinated by fig wasps, although some domesticated fig trees are sterile. Female wasps are only a few millimetres long and male ones are less developed and smaller.
A female fig wasp enters a fig and lays her eggs inside some of her flowers’ ovaries. In this process she sheds pollen she has carried with her from another fig. This pollen fertilises all the figs ovaries, not just the ones where she has laid her eggs, which allows them to develop their seeds. It is these seeds, developed from hundreds of flowers, which crunch when we eat the fig, not dead fig wasps, you will be pleased to learn!
After she has laid her eggs, the fig wasp dies and is digested by the fig, providing it with nourishment which helps mature the ovaries where the wasp hasn’t laid her eggs. When the wasp eggs hatch, the larvae feed themselves on the seeds in the ovary which means it can’t develop mature seeds. Eventually the mature male and female wasps mate with each other. The females have wings, and the males don’t. The females collect pollen. In some species they actively gather it in a specialised pouch and in others they collect it inadvertently. The wingless males are meanwhile carving a path to the outside of the fig. This is not for their own escape, they can’t fly, but to create an opening for the females to leave. The males die, trapped within the fig. The females fly out of the fig, carrying their pollen with them. They can sometimes travel more than 10 km in search of suitable fig trees. The cycle continues.
So, are we eating fig wasps when we eat figs? Technically yes because the male wasps remain inside the fig. However they are minute beings and are absorbed, like the female who laid them, to nourish the fig.
I think I still have lots to learn about my plants
I love learning about the plants and wild life around me and I can see I still have lots to learn. But it is amazing how many similarities there are between us and fruits and flowers. Will my CD’s stop the birds eating my cherries? Maybe it depends on who spots the cherries first?
I hope you have enjoyed my musings and please share any of your own stories and tips with me.
And if anyone who has studied with me would like to come to enjoy the land with me, I still have a few places left on my summer (August 23 to 27) Residential course here at La Source - Deepen your understanding of the Extraordinary Vessels: support for life’s cycles.