Fuji and Gala Apple trees: Can they polinate each other?
I planted a gala and a fuji apple tree in 2018 assuming they would pollinate each other. However, in spring 2019 I observed that they did not flower at the same time and I didn't see evidence of cross-pollination. Looking ahead this spring, if they don't flower at the same time again, is there anything we can do to achieve cross-pollination?
There are several reasons as to why the pollination (and flowering overlap) was poor, and it could be multiple factors acting simultaneously.
Fuji and Gala apples have many strains, not all of which bloom at the same time (surprisingly). If you can determine which strain(s) you may have, that would help in determining if they are supposed to overlap sufficiently. If the store where you purchased the plants doesn't know, then they (or you) could ask their supplier what specifically was being sold.
Flowering times are influenced by more than just genetics. Weather patterns such as cool, wet springs can cause flowering seasons to be compressed - where there is more bloom overlap than normal - and the season can be more spread out when conditions are different. Depending on how far apart your trees are and what microclimates they might be exposed to, this could shift flowering times. Frost pockets are low-lying places in the landscape where cooler air flows downhill and pools, thus making this microclimate slightly cooler than uphill sites. Even a few degrees difference can shift plant growth ahead or behind others. Similarly, a nearby wall or paved area can act as a heat sink, warming the area due to sunlight absorption and heat release overnight.
Cross-pollination in the absence of these factors altering the bloom time could be achieved by two approaches. Apple orchard managers use scattered Crabapples to boost pollination. If you try this, be sure to pick a variety that is resistant to common apple diseases so it doesn't harbor pathogens. You can also look at this pollination chart by a fruit tree specialist company and see if other apple varieties match well that could be added to your two. (Here it would be helpful to know which strains are being grown.) https://www.acnursery.com/resources/pollination-charts/apple-chart Adams County Nursery is a purveyor of fruit trees, though the bare-root mailing and planting season ends in a few more weeks. Area nurseries such as Sun Nurseries (Howard County) who offer regionally-appropriate fruit selections may also be a place to check for apple varieties that will be available later into the spring and summer because they will be potted.
Our resident orchardist recommends that, if you succeed in achieving fruit set this year, thin out all but one or two fruits per cluster once they have reached about the size of a cranberry. This is to prevent the tendency for some trees to enter "alternate-bearing" cycles, which means they fruit heavily (though fruit quality may be compromised) one year and skip the next. Thinning fruits tricks the tree into bearing fruit every year since it is being kept from fully reproducing to its potential; it also ensures the best quality of fruit as the tree has more resources to support each fruit instead of having to share among a large crop. Preventing alternate-bearing cycles from beginning is easier than trying to break the trees out of this habit once they have begun.