Planting a palm tree - Which soil should I use ?

cross-posted from: https://jlai.lu/post/2020342

cross-posted from: https://jlai.lu/post/2020236

I am trying to plant palm trees from date pits. I've already done it. It's a very long process that takes about a year to show a recognisable palm. The date pit has to be first immerged in water for at least 15 days and up to 3 weeks. Then in wet cotton for the same time. Finally, we can plant it. The palm should be water only when the soil is fully dry.

I've been using cactus soil last time but they are sold in big quantity and I don't want so much of it. Which kind of soil could replace it, preferably sold in smaller quantity? Are there soil especially made for palm trees?