How many is too many?

How many plants do you bring on after sowing? Do you sow 10% more and then pot on every one? Are you left with loads of spares, then waste water, compost and time on plants you will never be able to use? 

I have tried to cut down the amount I sow and be strict on the numbers I pot on. Although I still sow more "just in case"  I dont sow the whole pack, I try to stick with a number and then I worry I wont have back ups if a plant finishes flowering and I dont have anything suitable for its space.
Saved seeds are worse, I currently have several pots jammed packed with seedlings I need to separate. I tested Garett nicotiana seeds... I just potted on a tray with approx 100. 
What do you do with your extras? Do you have a plant area? Or are you mindful of the amount you sow in the first place.

I always sow a few more then I need flowers or veg . For several reasons 1 to allow for poor germination. 2 because I can’t help myself. 3 there’s usually someone I can pass spare on to or put them on my little sales barrow. Very rarely do any go in the compost, I’ll always try find a home somewhere.

With toms I usually sow a couple of extra seeds, cucs and courgettes I sow what I need.
Flowers are always easy to give away but no one wants veg seedlings here so I'm ruthless and compost the extras.

With toms and cucurbits, in the past I've usually sown 4 to a small pot then had too many. I can't be ruthless at seedling stage, I just can't. Then when I've possibly let the extras get leggy/potbound/starved and I have no room they get composted, no one round here wants them. This year I've only sown 2 per pot, which is a bit of a shame as I've found a pen pal from a few villages away who is willing to share. With flowers, where I'm no use whatsoever, I sow and fail no matter how many. Beans it's not the qty of seeds but the number of varieties that cripples me. I want to sow them all! Beans never get composted there's always a spot for a bean.
I've currently got two pots crammed with helichrysum that need pricking out, they'll all get a chance.

I always sow more than I think I need for tomatoes or anything else that needs an early start and I feel I won't have time to try again. The amount of over-sowing is gauged by source. Trusted seed companies and seed swap seeds just a couple extra, less trusted sources several more.

For big guys like pumpkins and courgette, I sow what I want and try again in a week or so if they don't come through. I never seem to sow enough peas or beans.

For tiny seeds, I just sprinkle and hope for the best.

I have neighbors on my street who will pick up any plants put out on the garden wall and friends at the allotment who will take anything else. Only my poor stewardship tends to cause the end of any spares not any intentional thinning or composting.

With tomatoes, I sow 4 of each in the hope that one will survive. If they all do, they're all planted.
With old seeds, I sow the packet as I don't expect many to germinate. However, the old leeks and old red cabbage have surprised me and I have about 50 cabbages and hundreds of leeks.
I can never grow too many courgettes or beans. Anything that germinates is planted out.
Most flower seeds are sown in situ and I hope for the best.

Just as every seed deserves a chance, every seedling deserves a life.

I have a general rule of one seedling per module/pot, so if I sow two or three seeds in a module/pot, then I thin them out to just one. The exceptions are things like sweet peas, peas, ipomoea, spring onion, beets etc. I also decide ahead how many plants I want and sow in an appropriate size module/pot. The whole seed packet is rarely sown at once.

As I've gotten older I've become more ruthless about it and spare seedlings get composted apart from tomatoes which are given away. There always seems to be a willing recipient for a tomato plant!

I always seem to sow too much and end up giving stuff away.  Our local Horticultural Society are always glad to receive plants/seeds etc that they can sell and our area do a plant/seed exchange once a year which is great.

I try to keep my sowing down to what I need - but often I think seeds have failed, sow more and then the first lot of little blighters pop up!
Fortunately my monthly garden club has a “donations shelf”, where you can leave your surplus stuff, and throw in a few pennies for anything you want for yourself.
The donations keep us all in tea, coffee, buns and cakes.

Just as every seed deserves a chance, every seedling deserves a life.

I can’t do that Veggie I just don’t have the space in my garden.