Answer: While Gala apples are listed as partly self-fruitful, you'll get a larger crop of apples if you have another, different variety in your garden. Gala is an early blooming tree so you should choose another early blooming apple tree to act as a pollinizer. The good new is that Gala will pollinate your second tree so you'll have double the harvest. Some of the potential candidates are Lodi, Liberty, Summer Mac, Yellow Transparent, Braeburn, Jonamac, Pink Lady, Honeycrisp, Cortland, or Granny Smith. I'm afraid your pear and peach trees won't help in cross-pollination but they will help in attracting bees to your orchard which will be good for all your trees.
Hope you have a bountiful harvest!
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