Thank you! That makes sense...now that you mention it...I have seen some gardens where that was done...I guess I assumed folks did that when they were trying to help newly-planted seed to germinate. But it seems not. So I guess the idea is to not only 'suffocate' the grass but prevent it from getting any nourishing sun...

BTW, my mom's home is in Boston. I've no idea the 'kind' of grass...didn't realize there were different kinds...it's just basic 'lawn' grass?.... blades of grass.... I'm picturing big bags of maybe... Scott's miracle gro or something grass seed in my mom's garage...from the past?

I'm quite sure it's not turf. Isn't turf like 'ready-made' rolls of soil/grass that are then rolled out and laid on top of existing dirt/soil? Yeah, it's definitely not that...I think it's just grass grown from seed that was simply thrown onto the soil...

Part of the yard is almost full shade...other parts pretty much full sun...but there's more or less grass in the entire yard...

Just be aware that if you live in a coolish climate clear plastic will not work. If I tried that approach the grass would not die. I would grow lusher, just as if it had been put into a greenhouse. Clear plastic works through heat not by excluding sun. Only black plastic would work here because the sun is not hot enough to solarise. It would work through light exclusion, not heat.

btw the ‘kind’ of grass refers to the species of grass, not the method by which it was grown. The same species could be sown as seed or laid as turf.

I had a long response typed out to this and somehow, somewhere, it just vanished! Trying again.....

You have options to removing a lawn without any chemicals. Which method you might choose will depend on how much effort you might care to devote to the project and how quickly you want the cleared area to be plantable.

1. Dig out the lawn. Cheapest method but most labor intensive. Also one way to be assured to get the best results as you can (and should) be as thorough as possible. Takes as long as it takes for removal....you set the pace.
2. Rent a sod cutter. Available at any equipment rental outlet and a relatively easy DIY project. Efficient and fast.......you will have a cleared, plantable area by the end of the day!
3. Solarization. As has been previously stated, covering the entire area to be cleared of grass with plastic and leaving it in place will kill off the grass. But it will take 2-3 months, will probably require some follow up and your front garden will look like a bit like a construction zone or termite tenting in the interim. You want to use black plastic for this, not clear! Clear plastic is used in solarization to kill off pathogens via heat but needs to be done in midsummer when the most intense sunlight is available. And is less effective for killing plants....for the reasons floral mentioned. To kill off grass and other weeds, use black plastic. This prevents sunlight reaching them and prevents photosynthesis. Without photosynthesis, the plants are unable to nourish themselves and they will die. Not a fast process.....allow 2-3 months in summer; 4-6 weeks in winter.
4. Smothering. Similar to covering with plastic, layering the area to be cleared with cardboard or layers of newspaper, wetting them thoroughly and then covering with a layer of compost or other mulch will smother the weeds/grasses and deprive them of both oxygen and sunlight and will prevent photosynthesis. Takes about 6 months for best efficacy but the process is fully biodegradable and you can plant in the interim by carefully cutting through the layers and inserting the plants. Will also improve the soil with the addition of the organic matter, so an added bonus!

A few additional thoughts. If you leave parts of the lawn intact, make sure you leave adequate clearance around any plants so the grass does not immediately invade. Trying to prise grass roots out or separate from any plant roots they have invaded can be a time consuming and Herculean chore! Also, if the remaining grass/lawn is not mowed routinely, you run the risk of the front garden looking and becoming a giant weed patch! You could be subject to your neighbors' criticism :-)

Both lawn and weed grasses are tenacious creatures and can have an ability to outcompete other, larger plants. If not fully removed first, they will come through any sort of groundcover and need to be carefully weeded out. Not all groundcovers will work equally as well and there is no such thing as an "all purpose" groundcover :-) They all have different growth habits and require different growing conditions. Your pachysandra for example wants shade only....it struggles and bleaches out in much sun.

And finally, by removing the lawn, you are opting for a higher maintenance landscape. Almost anything you plant will require periodic maintenance to keep the property from turning feral and overgrown. Lawns tend to take some of the least amount of maintenance of any type pf planting, especially if you do not insist on it being pristine and weed free. Covering any open areas with rocks or gravel is also pretty low maintenance.....but not NO maintenance either!!

And some terminology to help you through this process. A 'lawn' is a planted expanse of grass. And there are many types of lawn grass and where they are used for this purpose will depend on your location as to a suitable type. There are also many types of weed grasses. And you can also have a lawn that is comprised of something other than grass....like clover or thyme.

'Turf' is just another word for a lawn comprised of grasses. 'Sod' is the grass in its actively growing condition and this is what you can purchase in rolls to lay for an almost instant lawn. Or what you remove with the power equipment :-) Lawn grasses can also be planted from seeds and sometimes plugs or small starts. It depends on the type.

Thanks very much. A long read, by my quick assessment is that a sod cutter may be the way to go. Quick and efficient, and no having to source plastic and cardboard, etc. and then waiting. I assume the way a sod cutter works is that it is more or less 'splices' across the entire expanse of yard, removing the top layer of soil such that it includes the grass and any (likely shallow) roots?

Yes, I do know enough about 'lawn culture' to know that others in the neighborhood would not take too kindly to any untended lawn. I will be doing this only in the back, with the front being maintained in its usual way (my mom hires someone to periodically tend to it...)

Back to the sod cutter...so assuming we use it properly, we should have no reason to think any grass will make a reappearance, correct?

Correct. Make sure it is set so that it cuts below the primary grass roots....around 3 inches in most cases. You might get some sporadic, spotty regrowth but not much. You can go deeper with the blade setting but then you risk removing too much soil.

Also, mow your lawn as short as possible and water your lawn thoroughly the day before using the cutter.

Great last tip! I may not have thought of that on my own, but it makes perfect sense.

We had a large area of grass that I wanted to change to other plantings. We own a 5 horsepower chipper-shredder. In autumn, we shredded an extra amount of fallen tree leaves (collected from our own trees and also from the piles of leaves that neighbors nearby put out in the street for City pickup). We put down a layer of shredded leaves that was 6 to 8 inches deep in the autumn, and then, voila, we had an area ready for planting the following spring. This method is highly beneficial to the soil, which of course is the holy grail for gardeners.

I would advise actually not damaging the grass or soil life at all. Rather, research Charles Dowding and no dig method. It’s cheaper, easier and less time consuming.