First of all, you should research more about growing. There's plenty of time until summer so get busy.

Durban is a good plant. I don't know much about Malawi Gold but sativas usually won't yield high nor have a short flowering time. However, in the case of potency they're unmatched.

The location you described seems to be an excellent growing place, just make sure you won't be seen watering your plants.

Planting germinated seeds right into nature is a bit dangerous for them. Try using a cultivator or cover them with transparent plastic cups but cut a hole to let the seedlings breathe. You can also plant them in pots near your future garden, but put them in a safe place where snails and other animals can't reach them.

Insted of fertilizing, you should enrich your soil by mixing good potting soil or manure into it. In a very good medium, it is possible for plants to get on without fertilizer during their whole lifetime! And yes, fertilizing should only be done after four weeks. This is the average time when a plant depletes organic nutrients in an average soil.

Flowering begins at July-August depending on location and plant position. If you discovered a male plant early just cut it off, but if it's flowers are in an advanced stage of development you should burn or bury it. After the male has been cut, mature pollen sacks can open up when drying and pollinate your garden.

Have a nice crop!