A place to stay---just outside London, with lots of greenery

Richmond. Richmond Park is huge!!

Or

Chiswick (walk the Chiswick Mall ( River path) ).

If you chose Chiswick use the tube from Turnham Green to Ealing Broadway then jump on a GW train for a 7 minute ride to Paddington. All in 25 minutes

Tube from Richmond to say Tower Hill station
(across the road ) from the Tower of London about 45 minutes. Of take a train from Richmond to Waterloo ( 30 minutes)

Or look for lodging in Hampstead near the Hampstead Heath. Via the tube about 30 min.

Except Richmond, Chiswick, Hampstead are all IN London, the OP asked for outside London.

Lots of green parks is difficult. Any towns outside London are likely to have a station near the town centre. If you want to be in walkable distance of the station, you are not likely to have parks also in walkable distance.
You could pick somewhere small enough that you could walk outside the town, into the country.

• Hertford, Two stations, Hertford North and East. Typical English small town. Info on walks here: https://www.hertford.net/leisure/walking.php
• St Albans Info: https://www.enjoystalbans.com/walks-and-trails/
• Cambridge. Further out.

Many, many more. This is just a few towns I know. Smaller villages are even better for walks, but less likely to have hotels.

ONE BIG CAVEAT to this plan. All these are commuter towns. You will be travelling into London and out again with all the commuters in overstuffed trains, probably standing room only, takes time and not cheap.
For example, A weekly season, Hertford North to London Zone 1 (including the underground), costs £100.40

@Chris F

Gee thanks soooo much for the geography lesson.

Yes they are London suburbs. So what!?

Outside London? Yes!
Parks to walk in? Yes!

Accessible via bus or train? Yes!

Answered their question and the responses tick all their boxes!

If they are London suburbs they are in London, not outside. All parts of Greater London.

My interpretation of "outside London" is outside the conurbation, i.e. outside Greater London. I am not sure what the OP is looking for,however London officially, politically and how most people in England think of it is Greater London, roughly everything inside the M25.

It depends on your perspective - I would never describe Richmond and Chiswick as outside London. Almost everything inside the M25 orbital motorway fits my definition of London.

Many parks are locked at sunset or before. Nearly all towns have a park of some sort. If you stay out of London, you would find it easier to travel in after 9.30 when the rush hours abate. Commuting in can be an unpleasant experience if you aren’t used to it and be prepared to stand up for the entire journey in peak hours.

Sevenoaks has Knole Park, although this is National Trust owned. Tunbridge Wells has Dunorlan Park which closes around sunset and the Calverley Grounds for greenery.

Thanks for the replies. All the replies are welcome, both inside the city proper, and outside. We would love to know of quieter places with walking trails, and see some great ideas in the replies. Thanks also for the warnings about the crowdedness of commuter times.

How about the area near Kew Gardens? Are there walks outside the gardens, since I see some places to stay listed in that area?

Emma, how do you get the out os London feel without the commute? That, I think is what we would like but can't figure out where in London to stay, to have a walk in the woods (or a lush garden) outside our door, if possible.

We have done the British countryside and love it, but for visiting London, would prefer to stay in the city.
Take a look at Premier Inns. There is one near Victoria Station with great rates. You can walk to many of the main sites in the city.https://duckduckgo.com/?q=premier+inn+london+victoria&t=hp&ia=places

The Thames Path goes right through Kew Gardens, and extends for miles in either direction from there. And Syon Park across the river has more paths.

Ideas for some walks on the Thames Path near and through Kew:

https://www.countryfile.com/go-outdoors/walks/kew-gardens-richmond-park-greater-london/

https://www.theguardian.com/lifeandstyle/2006/may/20/gowalk.guardianspecial10

I don't know how crowded the train from Richmond Station to Waterloo Station would be at commute times, but the ride is fairly short, and the ticket with the National Rail logomwill give you access to the 2-4-1 offers for the rest of the day.

See Days Out London for more information on that.

Windsor is a bit further out but has decent walks in the Great Park and around Runnymede. There is also a full day worth of sightseeing with the Castle and Elton.
It is about 1 hour to Paddington by train with a change at Slough. There is also another line to Waterloo.

Richmond park is a wonderful oasis. If you are there in May/June don't miss Isabella Plantation (go there early or late). The park is open to pedestrians 24/7 except during the rutting season (there are tonnes of wild deer there) but cars are limited to daylight hours. You don't have to necessarily be based in Richmond as there are different entrance gates all around the perimeter. Another option for very walkable countryside with good train services would be Dorking (Box Hill and Ranmore common for walks)

Fenton! Fenton! ...Fenton the Labrador seals it for Richmond! Must-watch video, thank you Emma!

Oh Emma, that is hilarious!

Rebecca, terrific history! Thank you!

I can't even hear the name Fenton now without associating it with a stampede of deer! Although as a teenager who would spend many a late night in Richmond Park I have my own highlights!

What about Wimbledon? I lived right by Wimbledon Common for several years ... great place to walk -open all hours - there’s a lovely little cafe (it’s an old windmill) right in the middle. Also very close to Richmond Park. It’s easy to take the tube to see the sights.

Came here to recommend Windsor but I see it's already mentioned.

Fenton! Emma, that was quite a day-brightener.

Our last few times in London we have stayed out near Hampstead Heath...the neighborhoods are not "tight" like they are in the center of the city. The Heath itself is beautiful, very large, and great for walking and picnicking. There are several swimming ponds if that's your thing, and there are magnificent old trees with spreading branches. There are thickly wooded areas, large meadows, and rolling hills. Hampstead Village is quaint as is the Highgate neighborhood. You are only about 20 minutes from the "city center" on the tube. For the evening there are some really nice pubs that are very local as well as a number of nicer, upscale restaurants. I really enjoy staying in that area.

Anita, if you don't mind, where do you stay in that area. Is sounds wonderful.

Many parks are locked at sunset or before.

Given London's high latitude, sunset time is highly variable. If you're there in June or July, sunset is pretty late.

It's what no one would think of (and probably few would recommend) but we actually had a great stay out by the Queen Elizabeth Olympic Park a few years back. Hotel was picked because I could burn some reward points on a place that had its own kitchen and seating area, and we ended up in the same mega complex as the Stratford International train station and the Westfield Stratford City Mall and when we got back to our room at night, we'd eat our takeaway from the Greek place at the mall in our suite on proper plates, throw the dishes in the dishwasher and then go for a walk in the Olympic Park area because the sun didn't set until somewhere around 9:00pm that time of year.

We are still not sure where we would like to be for the first 3 days of our stay in England. When I explored the Windsor area and also Richmond, some reviews mentioned the sounds of aircraft coming and going.
Any suggestions of where to stay that is green and leafy, and either in London or outside of London an hour or slightly more, away, that does not have a lot of air traffic noise?

I never heard any planes in Richmond.

You’ve gotten a number of good suggestions.

Time to make a decision.