This is part one of a series on what I would do now after a dozen years of amateur apple breeding. In this part, I will discuss collecting parents, testing them and choosing what to cross with what.
Breeding apples is a long game and requires a lot of input on our part. Because of this reality, it pays to select parents carefully. I really prefer to choose both parents and will very rarely grow out seedlings that were open pollinated. If you have at least one good parent, then you can get pollen from me and I hope others will be offering pollen for sale in the future. Best case scenario is that we personally assess a lot of varieties and choose from among a bunch of good parents that do well in our area. I am the only one I know currently selling intentionally cross pollinated seed, but again, hopefully others also will in the future. Planting crosses someone else made is a better option than planting open pollinated seed, but it is better yet to breed with stuff you know does well in your area and inspires you in some way. I know it is exciting to get started right away, but consider the benefit of delaying a bit to be working with the stuff you choose yourself as inspired crosses based on personal experience. This opens up more possibility for breeding to your taste and to solve problems you have in your unique environment over multiple generations.
I spent untold hours researching and obsessing over apples to collect stuff. I have lots of notes and a still have a very long wish list. If I were to do it over, I would be more focused and collect more apples. I collected a lot, probably hundreds. Most of them are not very good, and not of any use to me in breeding. Research is useful and it is a way to find apples with specific traits like extremely long storage, disease resistance, hardiness, unique flavors etc. When I was doing most of that research over a decade ago, there was less information than there is now, so you are in a good position to ferret stuff out. For old varieties use search engines like googlebooks or archive.org that will search through old periodicals and books. For other general info and modern apples, just use a regular search engine like duckduckgo. I use the keywords apple variety, i.e. - Tewksbury Blush Apple Variety - I hope someday we have a truly extensive online apple database, with linked references. I’m happy to share all of my compiled research if someone actually does that.
It can also be extremely useful to ask other growers. This is especially useful when you have climate issues that are limiting, like disease pressure or extremes of weather. Yes there are apples that will grow in Alaska and apples that will grow in the desert and in the tropics. If you can contact any local growers that actually grow a lot of different apples, then do that for sure. Usually heirloom and diverse orchardists are stoked to talk shop and will probably be interested in your project. Don’t hesitate to ask, they can only say no. Another great resource is fruit forums. My favorite is growingfruit.org I’m sure there are others as well. The North American Scion Exchange on facebook is another good resource and you know those people are collecting lots of different stuff. When I am ready to start collecting again, I will spend some time in those kinds of places asking for recommendations on things like specific flavors, people’s favorite apples, season, disease resistance etc. Such a data base should allow for people to leave reviews and talk about their experience with apple cultivars.
The truth is though, that there are only so many people that have collected, and actually fruited, a lot of different apples. Chances are you will not find one in your area. There are also so many apples that who could grow and actually assess them all? Then there are also the matters of microclimate and personal preference. If you have room, collect a lot of apples and vet them yourself. Narrow it down with research unless you are totally insane, but at the end of the day, you won’t know until you grow. While it can be useful to get stuff that you know does well in your area, don’t assume that an apple from one place can’t perform in a place with very different weather. Apples from Ireland and England will likely not thrive in the desert, but there will be acceptions and some apples are very adaptable.
The ideal apple for breeding would have multiple desirable traits and be great for your purposes. If you are breeding for cider, you have a lot more leeway and might be looking for traits that make apples less eatable. I look for edibility and interesting traits. I especially look for unique traits, because that is where the future is and it is the funnest part. Once I have some idea of what the traits are, I stack traits between apples when possible, like red flesh on red flesh, or disease resistance on disease resistance. Think down the line a generation or two and start putting traits into lines now for use later. For instance, I do a lot of crosses with red fleshed apples and disease resistant apples. In a second generation, I could cross something like Grenadine x Goldrush with Rubaiyat x William’s Pride. That gives me two RF apple crossed with two different scab resistant apples and possibly some other disease resistance traits. I can take an offspring of either which has inherited scab resistance, and cross it with any random apple, and I do, but I figure stacking traits like that will probably increase my chances and the offspring from stacked traits might be very useful in the future.
There are a lot of different traits to choose from and the fun part is deciding how to mix them up. My tendency has been to minimize back crossing, which is using the same parent, or apples with a common parent, but backcrossing is a staple in plant breeding. A lot of plant breeding is actually just inbreeding. Instead I tend to stack traits from different apples. For instance, I could back cross Cherry Crush (Grenadine x Cherry Cox) back to Cherry Cox, but I would rather cross it to Chestnut Crab, which can have significant cherry flavor in some years. Chestnut is a better apple here over all than Cherry Cox and I get cherry flavor from an entirely different genetic line. The gene may be the same, I don’t know, but I’m just going to look for similar traits from very different lines and make the cross.
Some of the lines of breeding I’m most interested in pursuing are small highly flavored snack sized apples, savory apples, apples that hang in excellent eating condition into winter and eventually spring, red fleshed apples, disease resistance, unique specific flavors, very strong flavors, fruity flavors, musky flavor, very early apples that are actually useful and hopefully good out of hand.
Disease resistance is worth an extra note. There are only so many well known disease resistant varieties. If disease is a big problem in your area, which it is generally not in mine, do the research and get as many as you can that sound interesting and as many as possible from multiple breeding lines. I would take the best of these and pursue them all. So if you want disease resistant red fleshed apples, I would take multiple good red fleshed apples and cross them to multiple disease resistant apples as a first generation investment. Some will turn out great, but the real value will be in the improved offspring that you can take into the next generation. Because I hate reading research papers and I take a very dumb approach to breeding, I don’t know anything about dominant traits and how they are supposed to express in multiple generations. While that information may be very valuable and is surely available, I would avoid believing in any of it. You can still use it, but keep an open mind. More of that kind of information is unvetted than you might think.
Bringing disease resistance into apple genetic lines is a great service to many. Much of the world is plagued with serious apple diseases that cause untold amounts of extra work and losses. Keep your eyes out for heirlooms and any random apples that show disease resistance or are known to be disease resistant. Again, this is about bringing more diversity of genetics into the breeding stable. For instance, Court Pendu Plat is supposed to be scab resistant, but has probably been used very little in breeding work.
Here are a few links to info on disease resistance that took me about 10 seconds of searching.
https://blogs.cornell.edu/applevarietydatabase/disease-susceptibility-of-common-apples/
https://www.mehrabyannursery.com/growing-guide/apple-trees/what-are-the-most-disease-resistant-apple-trees/
https://www.orangepippintrees.com/search.aspx?ps=35
Pursue whatever inspires you or seems like it might solve problems you have in your area. I like crosses the best when they feel inspired and I can’t imagine that something good will not come from them. Sometimes though, you might have an exciting trait in an apple that otherwise just sucks or needs a lot of work and you’ll have to imagine that great apple a generation or two down the line. The more primitive and inedible the apple, the longer it will likely take to get something good out of its offspring. If you make the investment now, it may be someone else that can take advantage of it in the future. Some of the most exciting eventual developments are sure to come from taking chances on primitive apples that have unique traits, such as orange fleshed crabs.
Collecting scions has become easier and easier. There are groups and forums online where you can buy, sell and trade them. Eventually we will surely have a group for small scale breeders where we can communicate and exchange genetic material. The best places for trading I know of are again growingfruit.org and the North American Scion Exchange. I don’t spend a lot of time on forums or searching for stuff anymore, so if you know of resources I should include here, leave a comment and I’ll add them. There are also an increasing number of sites offering scions for sale and that trend is likely to continue.
The fastest ways to test apples for breeding are to graft to an already fruiting apple tree or by growing in closely spaced systems on dwarfing stock. Apples on dwarf rootstocks can fruit quickly. I have had good luck with bud 9, but there are a lot of different dwarf stocks out there now. If you need bulk rootstocks, willamette nursery and copenhaven sell in bundles as small as 50. Buy B stock if you can, they are cheaper and perfectly fine. It is also easy to grow your own rootstock. If starting a breeding project, you can save a ton of money by growing your own. You can also pull suckers out of your trial rows if they show up and use them. Avoid using random suckers from trees that may be diseased. Starting with certified disease free stock from a good supplier and growing just seedlings on them, you are pretty much sure they are clean, even when using suckers.
Video from Kuffle Creek on growing your own rootstocks.
If working over a fruiting tree, see my videos on that below. There are some mistakes you want to avoid making. For trialing a lot in a small space, I really like the diagonal cordon system. You can plant them as close as 18 inches in the row with rows 6 feet apart. You can also grow them half way up and graft a second variety on. Once they start fruiting, you can add scions to the side branches, which can fruit very quickly, often in the second year. All in all, it is a convenient, very space efficient and adaptable system that fruits very quickly.
In the next section, we’ll talk about pollination.
