Things about gardening that don't make sense

[GoggleboxUK]

Something hat has really puzzled me lately is that I've been watching all my Heucheras flower and drop their seeds and lots of other plants are about to do the same.

I also have a few flowers that are yet to come into bloom and I presume they will drop seeds in Autumn.

So why do we, as gardeners, sow seeds in Spring when plants naturally do this in summer and autumn?

[flounder]

Its all about timing. What we normally sow in spring, we give them the best possible chance of germinating. Seeds that naturally sow have to deal with the elements of winter. Admittedly, some things need the time to break down the germination inhibitors built in to the seeds, but we're just giving the odds a boost.
Having said all that, Its quite possible to sow them in the autumn, but then you have to give them optimal conditions over winter.
Thats my take on it

[jungle jas]

Yep I agree, some seeds you can sow straight away and they will germinate. Then you have a load of small seedlings to look after over winter a real pain in the rectum! However some seeds do need a period of cold to germinate, especially trees and shrubs. Hence the spring sowing. Of course this will not apply to many tropicals as they never see the cold.

[billo]

Googlebox, the short answer is we don't, it varies widely according to natural requirements.

In general terms, annuals will be sown in the Spring as they complete their life cycle in less than one full year. Most hardy perennials are sown mid-summer & many trees & shrubs in the autumn. Obviously there are exceptions but this is a good rule of thumb. Quite a few seeds e.g Primulas & many shrubs & trees require stratification before germination will occur.

The situation with tropicals is obviously different, in this case Spring sowing will be the norm as they clearly will not need or probably even survive a period of chilling.

[Conifers]

In the wild, plants produce thousands or even millions of seeds, and in general, just one survives and grows to replace each plant that dies.

In gardens, you expect to get a higher success rate than that so you maximise the chances of their surviving by sowing at the start of the growing season, rather than the end of the previous one, to avoid the winter attrition.

[GoggleboxUK]

Cheers people, some really good explantions there.

Makes much more sense to me now.