Natural pollination of Cannas

Canna pollination is basically trivial in practice. Hold a flower stem steady and smear some pollen onto the stigma of the style. Roughly six weeks later, there's a pod of ripe seeds if all has gone well. But there are some good reasons to know more and do more, because sometimes our efforts fail. Sometimes we want to do more than just a self-pollination, and make crosses between different cultivars, and sometimes even cross with species.

Pollination means transferring pollen from the anther onto the stigma of the flower. In the case of canna the hard part has already been done, and the pollen has been squeezed out of the anther and is waiting for us on the style. If we do not perform a hand pollination, then an obliging pollinator will almost certainly do it instead.

Pollen contains the male reproductive cells of a plant. Canna pollen, is heavy and sticky, and has a high protein content. It cannot be blown in the wind, so it must be gathered and distributed by insects or other active pollinators. You can laugh if anyone claims that canna gives them hay fever, as the only way you could get canna pollen in your nasal passages is to stick a flower up your nose. The plants trade some food to the bees in exchange for the transfer of pollen, called pollination.

The easy way
Most of the large canna hybridizers let the honey bees do their ad-hoc pollinating for them, although they do tend to isolate and plant varieties of interest together, this is why this blog pays a lot of attention to the honey-bee. The benefits of this type of planting are many:

• lots of seed.


• no worry about compatibility.


• no expensive hands-on care.

The downside is that only one parent is known for certain, and in our experience we have also found a much lower proportion of 'special' flowers. With hand pollination many more of your resultant offspring can be uniquely 'special'. The small, home garden hybridiser just doesn't have room for a lot of poor seedlings. On the other hand he or she can provide the daily attention that will yield specific crosses for specific goals and a high proportion of special blooms.

Further information on hand-pollination will follow.

Helping the pollinators

We have not had a good seed harvest this year, and we have automatically blamed the terrible summer we have endured. However, even if we have flowers in bloom we still need pollinators to assist when we are not there! Are we doing enough to ensure that we get enough bumblebees living by the collection? We have started planning ahead for next year to try and ensure we maximise natures natural pollinators.

Bees need flowers for sustenance, and our Cannas need bees for pollination. But it's important all the flowers we grow, not only cannas, provide the food that bees need. It's vital that we provide flowers throughout the bumblebee's life-cycle, straight through from March to September. Here in the temperate north, cannas start their flowering season in June, carrying on flowering until the frosts arrive, normally late October or early November, so that provides the goodies from early summer onwards. So, as canna growers, our gardens also need to provide flowers that will supply them with food from March through to June, when the Cannas kick-in.

The old Foliage Group varieties are particularly favoured by natures pollinators

So, the secret will be to try and keep continuous flowering, and it's also a good idea to have at least two nectar- or pollen-rich plants in flower at any one time during this spring period. The nectar feeds the adult bee, while the pollen is collected to feed the young. Of course, the more flowers you have, the more attractive your garden is to bees, so you can never have too many!

Most double flowers, especially modern roses, are of little use, because they're too elaborate. Some are bred without male and female parts, while others have so many petals bees can't get to the nectar and pollen to collect it. This is the main reason why Cannas are popular with many bees. So for spring we will have bluebell, daffodil, flowering cherry, forget-me-not, lavender, lily-of-the-valley, rhododendron, rosemary, viburnum, and thrift. For the early summer we have the early Cannas, fennel, lavender, passion flowers, thyme and vines, and then onwards there are always several hundred canna flowers open at once, so that should do the trick.

Let you know how we get on next year...