Raised beds and clear flat paths reduce the amount of bending and makes it easier to walk in the garden. Using a kneeling pad or a gardening stool with handles (to help you get up) saves on the knee and hip joints. Using long handled tools also helps to reduce bending. Good layer of mulch helps keep weeds down and moisture in, less weeding and watering.

I do most tasks only about 15 minutes and then switch to some other task e.g. yesterday I tilled a raised bed with a trowel for about 15 minutes then I switched to hoeing some weeds out back for about 15 minutes then switched to something else. In retrospect I don't know if this rush, rush, rush and get it all done and get stiff and sore and get sunburn and blisters was even good when I was 29 years old.

To make potted planters lighter, put styrofoam chips at the bottom before putting the soil in. It all helps! Marilyn

Yes I agree with Jane. When you're cooped up all winter and get cabin fever and antsy,the tendancy is to get it all done at once on that first nice day you get in the spring. The answer is to pace yourself and do a little bit at a time or your senior body will rebel. I posted a quote in another forum that I saw and it goes like this;
"But each spring...a gardening instinct, sure as the sap rising in the trees, stirs within us. We look about and decide to tame another little bit of ground." -- Lewis Gantt
It's the taming part that hurts.

Many "helps" for older gardeners are just plain ole common sense -- which only becomes 'common' and very obvious when folks get old themselves, like hub & me! Here are a few ideas (I hope they're not TOO similar to some good ones that have already been mentioned) :::

-- BEDS: Raised beds are good but we prefer actual BOXES, built only high enough for the gardener in question to sit down comfortably on the edge, and a bit less wide than the distance the seated gardener can comfortably reach across.
Or for a box that can be walked around, a bit less than twice as wide as the distance the seated gardener can easily reach across.
This goes for a person who uses a wheelchair too, of course.
Remember, the gardener won't be "just reaching" -- he or she will be working a good deal with hands or tools -- thus the "bit less than" the distance he or she can easily reach across. ... ...

-- PATHS: Should be as wide as possible (or affordable), should provide some traction even when wet, and as flat as possible especially for a person who uses a wheelchair, cane, or crutches.
Even for other folks, flat paths help prevent tripping. A decent width will allow for a good-sized sturdy garden cart to prevent endless trips back and forth or the need to hand-carry an awkward load of loose tools.
[Speaking of garden carts, those with large rear wheels such as 'bicycle' wheels seem to be much easier to pull or push than any other kind.]
Back to the paths: Especially for wheelchair users, hard surfaces are great :: professionally laid concrete; or large square or rectangular stepping stones with no spaces between (underneath, a layer of sand topped with heavy-duty weed-barrier fabric helps); or possibly that tiny very-hard-packed gravel often called "crush & run," often used for driveways.
Remeber that concrete should be brshed before it sets or have stones added to the top or some opther methid of improving traction especially when it gets wet.
BTW, bricks are good too BUT they can crack or heave unless laid/ mortared professionally & perfectly, which can be quite expensive.
For many older gardeners, a well-packed long-lasting *shredded mulch* path is fine.
A good-quality shredded cypress always did very well for us, with shredded cedar our second choice. Those woods last much longer than others we've tried, which reduces the frequency, expense, & bother of replenishment. ... ...

-- TOOLS: Some of the newer ergonomically designed tools and those made of lighter materials than the old wood-handled ones are great.
Also, as opposed to the usual short tools like trowels and hand forks, a well-made child-sized rake/ hoe/ shovel set helps extend reach when gardening sitting down, as from a wheelchair, or if turning-bending-reaching in a seated position is limited or painful.
There are also some specialty tools designed to maximize a weak grip or limited hand-arm mobility but I think those are available primarily through mail-order specialty catalogs, not at the average garden center.
Gardeners who prefer their familiar wood-handled or older tools or who cannot afford the newer ones can at least add something to the handles to cushion & improve grip and also to help avoid splinters for people who hate gardening in gloves (like me).
Some garden places sell special cushioned wraps or slip-ons, but here's something else that works: the fairly inexpensive narrow foam tubes made to insulate water pipes.
The foam is easy to cut with ordinary scissors, is pre-slit lengthwise, and can be well-secured to the tool handle with a little duct tape at each end.
However, because this foam is really an indoor pipe wrapping, I'd suggest it only on tools always stored indoors after use. ... ...

FOR MORE INFO:

You might find printed materials free or low-cost at your local county extension service.
If you don't already know where your extension service is, try looking in the county government section in your phone book -- in our phone book, the municipal-county-state-federal government section is the 'blue pages.' ... ...

You might also check your local library or a local or online bookstore -- or even a web search. Try topics like horticultural therapy, accessible gardening, barrier-free gardening, enabled gardening, lifelong gardening, or similar topics. ... ...

The four books below -- which we have & can recommend -- are several years old, but other newer titles (or perhaps newer editions of these) should be available :::

Easy Lifelong Gardening: A Practical Guide for Seniors - John Pierce & Roland Barnsley (both writers are seniors themselves) - Vermont: Trafalgar Square Publishing, 1993. [paperbound]

Accessible Gardening for People with Physical Disabilities: A Guide to Methods, Tools, and Plants - Janeen R. Adil (who became interested in accessible gardening for her daughter with a spinal condition)- Bethesda MD: Woodbine House, 1994. [paperbound]

The Enabling Garden: Creating Barrier-free Gardens - Gene Rothert, HTR (a wheelchair user and at one time President, American Horticultural Therapy Association & Manager, Urban Horticulture/ Chicago Botanic Garden) - Dallas: Taylor Publishing Co., 1994. [paperbound]

The Able Gardener: Overcoming Barriers of Age & Physical Limitations - Kathleen Yeomans, RN - Vermont: Storey Commmunications, 1992. [hardbound]

Sorry this is sooooo long but as I mentioned it's been a special interest of ours, and for reasons besides just our own age, lol.

It seems that the more information you can give them the more willing they are to try it and it may be for the first time. Would this be for yourself. I work at a home located within an Arboretum and work closely with residents. We have installed a garden with all kinds of elements. I found a large flat (used to soak air filter) container where you can have nmore than one using soil works well. If fits on a card table. Also a heavy metal table base can hold a hanging basket while they work. There seems to be no standard for wheel chairs heights so tables that can be lowered if needed is the key. I havent had them plan anything in the ground yet. I'm afraid they could get back up. We are having what I believe the first national meeting for the hort. therapy. It should be filled with all kinds of new products and gadgets. I hope this has helped. Deb Lux

Greetings to all:
I know that this posting was titled, Hints and aids for older gardeners, but all the ideas that have been listed are also super useful for physically disabled person of all ages! Thank you for caring and sharing as you have!

Here is a link that might be useful: chta

Ditto a couple of suggestions above i.e. raised beds and switch tasks often: I also switch tools often e.g. an ordinary hoe for a while then a triangular hoe for a while. Additionally I always wear gloves when gripping anything like a hoe or a watering can, an old arthritis doctor told me that trick long ago before symptoms of arthritis; he said it was just the ergonomic thing to do.

I would like to see a separate forum on this topic. I am posting this thought on the suggestions forum, so anyone interested could support it there if you wish. I never thought of looking under the education forum for these ideas. Accessible Gardening, Tool Shed, and Tips and Techniques are places I looked before searching "seniors" just now. I like the label of Simplified Gardening for the Young at Heart.