Remember to rotate your crops from last season if possible. Also do not crowd your plants. Insects and disease love places that are overcrowded with no air circulation. Spacing your plants will limit the areas for the bugs to hide.
There are many organic options to keep insects and disease under control. For insects, use Insecticidal Soap for soft-bodied bugs, Spinosad for beetles, caterpillars, and leafminer. To prevent powdery mildew on curcurbits and cole crops, use Serenade or Neem Oil, when it comes to disease, it is always easier to prevent than to cure. Also, mulching the garden with Hardwood Mulch or Pine Straw will keep fungal spores from splashing up onto the plants.
Fall can be the best season for growing vegetables due to the cooler weather and more rainfall, unlike the spring garden where we are heading into the hottest season. So plant now, space things out, keep the garden weed free, fertilize regularly and be a good bug scout. And remember, only spray insecticides if necessary. We do not want to kill the bees or other pollinators in the garden.