When starting out it can be hard to nail everything in the garden all at once. We put a few rules of thumb in place which we find helpful when we start a new garden. One of them is this rule for watering the veggie garden:
Water 9 Litres per Square Metre, per Week
This is obviously a generalisation as not all gardens are the same, but when you're starting your veggie garden this is a good rule of thumb to stick to. The actual amount will differ depending on the following variables:
As gardeners we observe and interact regularly with our gardens, and in doing so we will see when they get stressed out with too much water or too little water and will act accordingly.
If you're ever in doubt, ask your garden. 😁