It has just occurred to me that growing conditions in the UK are quite different to those i am experiencing here in California, and my frequent references to the Love Apple Farm blogsite may be causing some of you Brits, and folk elsewhere in the world, to take what is written as correct for you.
There are several things that come to mind as considerations:
Planting things deep into the soil may be fine here, where the ground tends to be on the dry side, but will probably cause rot and disease to the stems in cooler or wetter climes.
Constant hydration (watering) to keep the potting soil wet at all times is now always advisable. Allow the surface of the growing medium to dry off between waterings is advised where humidity and temperature differs.
The season starts much earlier here than it does back home, so adjust sowing and planting dates accordingly. Surprisingly the last frosts are expected here on the farm at a similar time to those in southern England. The days, however are much warmer here.
More tender crops, tomatoes, peppers, melons etc do well outside here with plenty of daily warmth, many will, unfortunately require the help of a greenhouse or polytunnel elsewhere.
I don't want to put you off from trying, just to consider differing climatic conditions before proceeding exactly as suggested on the blog.