You might consider switching from a conventional garden laid out in rows to raised beds which will avoid much work and back strain. Beds three or four feet wide allow you to work the soil and care for plants without ever standing on it. They can be any length, depending on the area available, but a cross path every 20 feet or so will prevent the need to walk a great distance to get to the other side of the bed. Adding compost, manure, and topsoil to the bed raises its level, and many beds are framed with well aged railroad ties or landscape timbers. The deep, rich soil in raised beds permits intensive planting.
Less room is wasted on walkways in raised bed gardens.
Save space with the use of fences or trellises for cucumbers, tomatoes, and pole beans. Take advantage of all of the time available to you for gardening. Plant cool season crops such as spinach, lettuce, and cole crops both spring and fall. Plan to precede a warm weather crop such as tomatoes with a quick growing cool season crop such as lettuce. Cool season crops such as peas can be followed by quick growing warm season crops like bush beans.