Great advice Marty, but why not consider to try an organic vs salts grow @ArtVandalay . Here is a recipe that could help you:
This soil mix taken from Reefermans soil recipe and added a couple extras.
1 part composted horse manure
1 part coir and perlite mix
1 part top soil mix
I also added potash, biochar and worm castings. Sweated like a pig on a hot first of spring day. I got about 30 x 20 litre bags filled with the soil mix and letting it chill for a couple weeks. Lined up in the orchard where it gets good sun and easy access to water.