Verbena

Can anybody suggest what I can do to get the best out of this year's sowings of these seeds?
For the past two years I have sown a tray of these fairly early on a kitchen windowsill but have only had a few of the seeds germinate. Should I perhaps leave the sowing as late as possible or are these seeds just generally difficult to germinate?

 

J bt H picked this info up may help,
VERBENA (Verbena hybrida)
TYPE; Half Hardy Annual
SEED COUNT; 400 Seeds Per Gram
FOR 1000 PLANTS; 5 Grams
WHERE TO SOW; Under Glass
SOWING TEMPERATURE; 20C
WHEN; March
TIME TO GERMINATE; 3 Weeks
TRANSPLANT; 2-3 weeks
FLOWERS; June-October
There are different types of Verbena some require stratification

 

Thanks Walnut. The seed packet I have says sowing time is Jan-March but, in the light of other information given elsewhere on this site I have decided to delay all sowings until early March. Perhaps my Verbena will benefit. I do think that they are lovely plants!

 

Jack, Verbena seed can be a bit fussy. The RHS seed scheme recommends cold stratification for two weeks (ie put in the fridge for two weeks).

My own experiance of Verbena bonariensis, three years ago, was sowing in seed trays then when they did nothing I put them in the fridge for two weeks. On removal from the fridge they still did nothing for 3 or 4 weeks, and I was just about to chuck them out, when one day I looked at them and suddenly all 500 seeds had germinated simultaneously. So I suggest cold and patience.

 

PeterS, silly question perhaps but does the seed need to be sown, therefore moist, before stratification or will it work if you put the open packet of dry seed in the fridge (and does that mean the freezer or just the cold compartment)?

 

Jack the seed needs to be moist. You could just mix them with a little moist compost or sand in a polythene bag, and put the bag in the fridge for a bit. It must be the fridge part and not the freezer. Then, after removing them, spread the mixture on top of compost in a seed tray.

You could even put moist kitchen towel in a sealed polythene bag and spread seeds on top of the towel - I have germinated many things that way. The disadvantage is that you have to remove each germinating seed manually with a pair of tweezers. But the advantage is that you can have a stack of bags that take up very little space. Its a good way to test seed viability. Its surprising that seeds can grow into two inch seedlings over three of four weeks with no nutrition at all - just stuck in a sealed bag. I used to just blow into the bag each day to ensure they had some carbon dioxide. - but I digress.

If seeds are kept quite dry, you can store many for years in a fridge and even tens of years in a deep freeze. Its a recommended method, but doesn't work for everything.

 

Many thanks for this information, PeterS.
The paper towel idea is a very good one.
I'm wondering, though, if sowing was done in a conventional way in pots of compost whether the same "stratifying" effect couldn't be achieved by leaving them outside throughout February in a cold-frame or other sheltered place?

 

Jack. The answer in general is yes. Allium seeds need startifying, and that is exactly what I have done - left them outside in a cold frame, and they are already germinating. But Allium are pretty hardy.

If you were growing Verbena bonariensis or V. rigida or V. hastata - I would say yes to that too. That is how they germinate naturally. But if you are growing half hardy Verbena hybrids, I don't think the seedlings would like the cold. In fact I am not so sure about the need for stratification with half hardy hybrids. The principle of seed germination is that you provide the same conditions that they would experiance in the wild. If they are not hardy - they may not experiance that naturally. But then if they are cultivated hybrids - they don't exist in the wild.

What type are they?

 

They are "Verbena hybrids" Verbena Sparkles mixed from Johnsons seeds.
As there are a lot of seeds in the packet, I think I shall try making several sowings...fridge, windowsill, coldframe...and watch to see which ones do best. I shall save the majority of the seeds for the windowsill sowings as you suggest that hybrids might resent the cold.
Thanks for the suggestions.

 

Best of luck Jack. I agree with you, I am all for trial and error. That's a major way you learn, and it's always worth keeping records.

 

I thought I'd just report back on some results I've had.
When I read Peter S' post on 16.1 I confess I went ahead without thinking and put some moist seed in the freezer compartment before I began to think I had been stupid and asked for further advice about stratification.
A few days later I removed them and sowed them in a small pot along with a handful of other verbena seeds in a different pot. Both sowings have now germinated and it looks like the frozen variety might have enjoyed a better germination rate than the others!
I am pleased about this, because in the past I have found verbena seed difficult to germinate. Perhaps the seed supplier was at fault.
I shall make a further sowing in March and watch to see if the earlier sown seeds perform differently to these.

 

How strange - I just bunged some seeds in a tray of compost and left them - I had around 80% germination and still have a whole host of them in the garden. Must have been beginner's luck!

 

Jack - thats very interesting. I don't think a short stay in the freezer will actually harm seeds. That's what happens in nature with frosty periods lasting several days or even weeks.

Daisees - I presume you are talking about Verbena seeds. Seeds from most other plants don't need a cold period. I think there are no hard and fast rules. I've found seeds can germinate over a wide range of conditions (if they want to!). Last year I put some primula seeds in a heated propagator without thinking. Then found out they should be left to germinate in the cold. But mine still germinated.