We have an old house with an unusually wide (for a small Victorian terrace, anyway) garden - around 50ft in length and a good 30ft wide. Most of this is lawned with borders but we also have a large decked area with lots of stone tubs and pots.
I must admit I do very little in winter other than the odd bit of a tidy up, but from April/May onwards I definitely have a routine for some things:
- lawn mowing / strimming lawn edges / weeding borders once a week
- watering (tubs/hanging baskets/new plants in borders) every evening unless we have had rain. Would also water borders during prolonged dry spells in high summer.
- dead-heading/pruning etc probably every week or so until the spring flowers have finished
- new planting as and when the mood takes me!
I would say on average I probably spend a couple of hours a week, but that's based on getting out there most days and doing bits and pieces. I have very deliberately planted a fairly 'low maintenance' garden though. Other than spring bulbs (mainly daffs, irises, crocuses and tulips), we never have any bedding plant flowery kind of stuff, and we don't grow any veg apart from a big terracotta trough of herbs. We went for lots of pretty shrubs with varying colours of foliage (hebes, azaleas, pieris etc etc) and greenery (ferns, box, mini conifers, bamboo and so on) with a few small trees in big striking stone pots (apple/cherry/olive) and a couple of acers to add dramatic colour.
So I think for me that's been part of the key to keeping on top of it - planting stuff that, as long as it's kept well hydrated, pretty much takes care of itself.
Regarding weeding - the best thing I did to help minimise weeds was to spread barkchips in between all the plants in the borders - as a result, I only ever have to pull out the odd weed here and there, like literally a minute or two when I notice them.
Oh and we have a lawn treatment company do the lawn maintenance stuff for us. Which is probably cheating
but it does mean the lawn looks good for no effort on my part.