Improving the germination rate of French beans

[Primrose]

I'm never very successful at getting a good germination rate with my French beans (dwarf or climbing) and this year am trialling putting them on damp kitchen tissue for a while before putting the into compost to see if they will start sprouting. In previous years my seeds have often rotted in the compost & I never seem to get the moisture level quite right.

Has anybody tried this and does it work? Or do you have any other tips on how I can improve my germination rates?

[pongeroon]

Hi Primrose,

I had the same problem for some years; last year I tried planting in modules and when these failed I re-planted, and planted direct too, with poor results. Then I planted direct again, by which time it was about the end of May. Success!!! As many beans as we could eat, and I filled the freezer. So I shall not be sowing them until late May again.

[Primrose]

Yes, I'm beginning to think that temperature is also a big issue in germination so although I've got some advance beans soaking on damp tissue, I'll delay sowing my main crop until later.

[alan refail]

Yes, I'm beginning to think that temperature is also a big issue in germination.

Morning Primrose

Temperature is the crucial factor. Best practice is only to sow when the soil temperature (and that includes pots/modules) is above 50F/10C. Colder and even good viable seed can rot, or at best struggle.

[Primrose]

Alan, thank you for that temperature guidance. I shall keep my thermometer handy this time and hope for better results. I've got a few seeds trialling between damp kitchen tissue on the window sill and if they sprout will keep the sown pots indoors or in my plastic greenhouse until the temperature rises.

[sally wright]

Dear Primrose,
there is another thing to watch for which is that the bean seeds have been packeted too dry. In practice what this means is that the seed needs to regain it's natural dormant moisture level before starting to germinate. This can result in the seeds beginning to rot before they have a chance to grow. So open the packets about a week before you plan to sow them. This can also affect other seeds especially cucurbit seed.
Regards Sally Wright.

[adam-alexander]

I only grow climbing varieties of French Beans and always start them on damp tissue in mid-late April, until they sprout, then pot up and grow on either in the kitchen or the sheltered cold frame. Plant out no earlier than late May even then sometimes need to wrap the wigwams around with fleece. As Alan mentions temperature is crucial - these are sub-tropical plants from central America originally.

a-a

[Marigold]

Thank you for this thread; thought it was just me last year, and yes, later sowings succeed finally.

[Beryl]

French and runner beans are notorious for rotting if sown too early.
Mid May onwards I think is early enough. Very good tip from Sally - thank you.

Beryl.

[FelixLeiter]

I have good results sowing in the first week of July. Of course, this means that you're not picking beans the whole summer, and I do a spring sowing too, but this late sowing germinates quickly and evenly in the warm soil and benefits from the weather being more consistently warm. Growth is rapid and the beans start being produced in September and will carry on until the first frost, although production will slow before then. I have grown huge quantities of quality beans this way.
Regarding varieties, I consider those skinny Kenyan beans (such as the variety Safari) to be a waste of time and effort. What a lot of fiddling around is involved to gather a small quantity of rather woody beans. I much prefer a variety with a nice fat pod. You don't need to pick many for a good helping, and they're juicy and full of flavour. My favourite is Sprite, from Kings, which seems less cold sensitive than others.

[Lurganspade]

.

Hi,

At the moment I have four pots with three plants in each between four and six inches high,growing in the greenhouse!
I am trying for an early crop, half green and half yellow podded plants!
I have done this for quite a few years now!

I find that the yellow podded are less likely to rot than the green lot!
I soak the seeds over night to get them nice and plump!

What I plant them into are the long tall fresh double cream tubs, with lots of holes drilled in them, half filled with damp not wet compost,then about an inch of slightly damp sand on top, again not sodden wet!

I push the seeds (about three or four) on end about half way in and the other half not covered,and then place in a heated propagator!

It is easy to see if they are germinating or rotting, the rotters I get rid of and as the others throw out roots I trickle some dampish sand over them to keep the roots covered, then when they have thrown a stem with leaves I top up with proper compost!

To keep the seeds moist I lightly spray when they look dry, fiddly but so far succesful!

I have some others with their leaves on to plant under cloches later, if we escape any late frosts then we should have some more to follow on with!

I have never managed to germinate any this early without heat!

Hope this helps!

[Primrose]

That's a really interesting insight, thank you!

I was a little worried that soaking the beans completely overnight might have been too much but it obviously works for you if yours are already sprouting.

I was surprised to notice that of the two yellow varieties I've just bought, one variety had white seeds and the other black. I wonder if that makes any difference at all to their rotting vulnerability?

[Primrose]

Well I'm pleased to report that all my white skinned yellow French beans have now started to produce tiny shoots between the damp kitchen tissue. The black skinned ones are lagging behind a little (the seeds are slightly smaller) but look as if another 24 hours will see some shoots from them too.

If I can get good plants from this method it will eliminate my annual dilemma of wondering whether the beans sown directly into trays or pots are rotting beneath the compost or just being slow to germinate.

[Myrkk]

I don't have a problem with germination... all bar one of the 7 I planted germinated. However, once they started to get their first set of true leaves they dropped their "baby" leaves and then proceeded to stop growing... any suggestions?
They were kept in a propagator.

[Johnboy]

Hi Myrkk,
Your beans have either damped-off or maybe they have been eaten by mice which is their favourite trick. If mice not involved then damping of is probably your problem.
If raised in a propagator they need plenty of ventilation at all times and without ventilation damping-off will occur very rapidly.
JB.