Apples In Bloom: Tips for New Fruit Tree Growers

Over the last few weeks, the apple trees I purchased in January, 2010 began blooming.  I'm a newbie when it comes fruit trees and made a number of mistakes.  In this posting, I'll let you know the mistakes to avoid, guidelines on growing apples and tips on how to select apple and other fruit trees for your garden.

How To Mess Up Your Apple Orchard

In late 2009, I decided to add apples and other fruit to my garden.  So I cruised the internet searching for advice on the best apples using Google and search terms such as "Best heirloom apples," "Best tasting apples," "Top apple varieties" etc.  The search yielded plenty of exotic apple varieties of which I had never heard.  The descriptions were incredibly tantalizing; for example here's a description of the Spitzenburg apple taken from the Trees of Antiquity web site:

Thomas Jefferson's favorite apple. Un-excelled in flavor or quality, the fruit is great off the tree, but flavor radically improves in storage. Medium apple with crisp, yellow skin covered with inconspicuous red stripes and russet freckles. Flesh is tinged yellow, firm, aromatic, and complex in flavor; a perfect balance between sharp and sweet.

The internet research opened up a whole world of apples of which I was completely ignorant and I went on an apple buying binge, ordering a variety of sweet dessert apples and and ones that are either sharp or bitter-sharp tasting that are used for making cider.

As it turns out, most of the apples I purchased are heirloom varieties with English or French origins.  The varieties I wanted were grafted onto root stock that would make them semi-dwarf trees.  I reasoned that placing them in pots would further stunt their growth, making them easier to maintain in a home garden and they would probably yield more fruit than the patio sized trees you typically see pictured in pots.

When the fruit trees arrived in January of 2010,  I planted them in 25 gallon smart pots. These are fabric pots that drain well, keep roots cooler than traditional clay pots, and allow more oxygen to circulate into the soil.  Smart pots can be purchased in a variety of sizes.  I started my bare root trees in 25 gallon pots and moved them up to 35 gallon pots this spring before they went into bloom.

So Where's the Problem?

Only after my initial burst of enthusiasm and tree ordering binge did I do more detailed research on creating a home apple orchard.  And there was a nasty surprise waiting for me....There's an old saying among carpenters - Measure twice and cut once.  Well I should have done a little more "measuring" before I ordered my trees.  Here are the issues:   

Chill Hours:  Apple tree varieties have specific "chill hour" requirements -- the number of hours each year when the temperature is below 45 degrees Fahrenheit. Trees that don't get the proper number of chill hours don't have enough of a dormant period to produce fruit. Some apple varieties such as "Anna" have minimal (200 hours) chill hour requirements, while others such as "Northern Spy" require more than 1,000 chill hours.  Most of the trees that I purchased (Ashmead's Kernel, Cox's Orange Pippin, Orlean Reinette, etc.) have high chill hour requirements. (+800 hours)

Problem #1: I barely have the proper chill hours to grow the high chill hour apple trees that I purchased.   I would have been better off selecting apples with far fewer chill hours - 200-600. 

Root Stock:  Fruit trees are sold on a variety of root stocks that effect their growth habit.  You can buy standard sized trees, dwarf, semi-dwarf and ultra dwarf varieties.  Ultra dwarf trees grow to about 6 feet high and can produce 30-40 apples, Dwarf and semi-dwarf trees grow between 8 and 18 feet in height respectively and produce about 3-4 bushels of fruit.  Standard sized trees grow to 25 feet and can produce 20 bushels.  The terminology is not really standardized and made more complex by the fact that there are many different root stock and scion (fruit bearing part of the graft) combinations that yield different sized trees.  I've even seen some some trees referred to as "semi standard," where the writer described a tree size category that fits between dwarf and standard.  The bottom line is that you need to be careful about what you purchasing.  When I placed my apple tree order I was under the impression that I was buying trees that would grow to about 8 feet in height.  The reality is that semi-dwarf treed under normal conditions should grow to 12 feet or higher.

Problem #2:  The trees I purchased are grown on a semi-dwarf root stock called M111.  In the ground, apple trees on this rootstock normally will grow 12-15 feet in height.  I really should have purchased trees on a dwarf root stock or ultra dwarf root stock.  It's difficult to asses what the height and yield of my trees, but I fear a double whammy - trees too big yielding paltry amounts of fruit.

The bottom line -- it is really difficult to predict whether the trees I planted  in pots will be decent producers of fruit.  There are just too many variables -- varieties with too little chill hours, offset by a maritime climate in Northern California that has very cool nights, semi-dwarf trees that are technically too large to be put in pots, offset against the use of unusual pots that are supposed to provide better oxygenation of the soil and drainage. 

Results So Far

After a rainy cool winter the weather has finally turned.  My apple trees did bloom this year and I can tell that some have set fruit.  The variety that bloomed first and most profusely for me is Cox's Orange Pippin (see photo of immature fruit set on my tree).  Cox's Orange Pippin is reputed to produce one of the best desert apples available.  It is also known to be very difficult to grow, even for experienced orchardists.  Yet this is my best tree so far. Go figure.  Over the next few years, the trees will come into maturity and I'll know whether my first foray into fruit trees will truly be a success or a bust.

Recommendations for Newbie Fruit Growers

• Planning:  Buy a book or do internet research on fruit trees before you purchase.  Learn which root stock are used to make dwarf varieties.  If you are growing other types of fruit you should also determine whether these trees need pollinators and the timing of their bloom.  For example, most cherry trees need to be pollinated by another cherry variety.  That means you'll need to purchase two trees that bloom at the same time in order to get a crop of cherries. (For example, Bing cherries are often pollinated by a variety called Ranier)
•  Chill Hours:  Chill hour requirements exist for apples and many other types of fruit; just do your home work before you buy.  Do a Google search for the name of your community plus "chill hours."  Alternatively, seek guidance from your local garden center or a master gardener, or agricultural extension agent in your area.  Incidentally, there is some disagreement among experts as to how to best measure chill hours, the tolerance of various fruit trees to warmer conditions, and whether published data on chill hours is out dated due to the influence of global warming. Because of all this uncertainty, I would recommend that you select varieties that have chill hour requirements that are are at least 200 hours less than the published chill hour statistic for your local community.
• Tree Height:  In my opinion, the terms used to describe tree height in nursery and gardening catalogs are confusing and not terribly helpful.  In some catalogs a "dwarf" tree is an ultra dwarf patio plant while in others it could mean 25-35% of the height of a standard tree.  The ultimate size of the tree depends both on the root stock and the variety that is grafted to it.  In my opinion, it would be better for suppliers to specify the height range for each tree in their catalog.  Since they don't, check out this tree height calculator at OrangePippin.com.  Just enter the root stock (this is usually mentioned in nursery catalogs), variety vigor (available at OrangePippin.com) and your soil quality (take a guess or play around with various combinations to see how it impacts the size of your tree). The calculator will estimate the height of your mature tree.  Even if you have lots of space, you may want to limit your purchases to dwarf or ultra dwarf trees.  Their smaller size makes harvesting fruity much easier.

I welcome comments from experience fruit tree growers. 

Photo of Cox's Orange Pippin

Comments

[David]

You might want to check out Kuffel creek
http://www.kuffelcreek.com/apples.htm
He grows and sells apple varieties for southern california and is based in Riverside which is inland and very hot with few chill hours. He seems to think that the chill hours requirement is not as simple as it sounds and seems to have success in this climate. He currently uses M111 as he thinks the heat in itself has a dwarfing effect. I imagine Palo Alto gets pretty hot as well but not that familiar with the area.
Hope you are successful with the Cox's orange as they truly are the best tasting apple I've had, although a good russet is also nice. Don't know why they aren't grown in US as somewhere there must be a good climate for them. Up in the mountains here in southern cal there's a small apple growing area and we always used to visit this old guy who opened his orchard and had a few Cox's oranges, used to get a few a year. Haven't bee there recently as last time we went he was very old and I fear that he's probably not here anymore.

[H. Mark Delman]

Hi David:

Thanks for the heads up on this. Its an interesting web site. I may get the book that Kuffel Creek is promoting and check out his recommendations. The Chill Hour requirement may be a reasonable starting point, but not a statistic that shouldnt be used without further considerations. It reminds me of BMI or body mass index, a measure of your weight to height that is supposed to tell you if you need to lose a few pounds. The BMI works well unless you are in fit.