While permaculturists will always try to grow their crops in relation to the rhythms of nature, a couple of unobtrusive tweaks could help a great deal in extending the growing season beyond what the forces of nature dictate. For example, if you start your seedlings using a conservatory or a greenhouse while the frosts of winter are still in the soil, you’ll give the seedlings a good start when transferring them outside during spring. This means that they will be ready for harvesting earlier than expected, paving way for succession planting. The use of mulches and cold frames can also help to extend the growing season by providing protection against winter frosts and first fall. This means that you could harvest for a few more weeks.
While increasing your bed’s edge leads to increased cultivable land, the same principle is applicable when it comes to height (even though not all permaculture farmers are aware of this). So, it is great to mound up your bed soil into an arc-like shape rather than work with a flatbed. This will definitely increase the surface area for growing your crops.