Vegetables are heavy feeders, they need nitrogen when they are growing the vines and potash as they come into flower. So a compost based on cow dung or poultry is good for that, but make sure you add a lot of carbon to the heap as you make it... leaves, dry grasses etc. You may also soak urine into dry high carbon matter. Make Biochar for this as it adsorbs ammonia really effectively so you really don't get a smell. Biochar is simply charcoal made at a high temperature (550 deg c), the key is all the volatile oils and tars have been driven off and combusted leaving behind a pure carbon residue. It should tinkle almost like glass if you have made it well. You can actually crush this and feed it to chickens, and if you can gather their droppings you will have bio-inoculated soil improver ready to go, or soak it in a compost tea for a couple of days before you use it. Potash is of course available in wood ash, there are plants that will hyper accumulate potash also. Integrated Pest Management – IPM, builds an ecosystem that favours vegetables. If you are getting aphids or other sap sucking bugs then you can paint them with a flour and chili mix, many remedies. But more importantly deliberately create habitat and add plants and trees to encourage birds, bats, lizards etc, those things that eat insects in large quantities. This will improve phosphate cycling also. Look into seed saving from vegetables, they are one of the easier plants to save seed from. Keep varieties apart so they don't cross. The key hole bed also encourages continual feeding with food scraps and grey water from washing pots, this helps create behaviours around valuing waste by providing locations for it to go to.