Planting An Apple Tree

Although planting a tree seems simple, I wanted to share my process for working in our local Stafford, Virginia clay soil.

First, A Note On Soils
Soil is made up of a combination of sand, silt, clay, and organic matter. Sand, silt, and clay are the mineral components. Sand particles are relatively large; sandy soil drains quickly, but holds nutrients poorly. Clay is the opposite end of the spectrum, with microscopically small particles that are capable of holding onto nutrients and water really well. Sometimes too well. Clay has a nasty reputation for poor drainage.

Lots of people know that a balanced combination of sand, silt, and clay is called a 'loam', the holy grail of garden soil. (Almost nobody has loam naturally. Especially in urban/suburban areas.) People also make a big deal over whether there is too much clay, but what most people don't know is that the soil structure is far more important. When I say structure, I mean the way that the tiny soil particles clump together into aggregates to allow pore space.  Pore space allows water and air to penetrate the soil.

Pore space is important because the way you transform clay into a brick is by removing pore space (and then adding heat that change permanent). So, when you work with clay you want to make sure you preserve soil aggregates and the pore space they create.

Three Surefire Ways to Destroy the Structure of Clay Soils:
1) Compaction - do you ever remember working with clay for art in grade school? Do you remember your teacher telling you to pound the clay to get all the pore space air bubbles out of it? Well, the equivalent of this in your garden soil is put a lot of weight on your soil. Especially repeatedly and/or when it is wet. When your soil is sopping wet, don't drive heavy things over it. You want to be careful about walking on it when it's really wet too.

Btw, the reason why suburban and urban soils is so bad is because first, they scrape away all of the original topsoil leaving the subsoil. And second, the developer proceeds to run backhoes and all sorts of other heavy equipment all over it  - in all weather. Any pore space that was originally there gets pounded out before you ever move into your home. This is why I've met so many people who have trouble growing grass at their new luxury home.

You can see the mark where the pitchfork tine has
sheared the soil, making it look shiny and as smooth
as pottery. You want to minimize this. Note how the
rest of the area is breaking into crumbles. With a
shovel, the entire surface of the cut would be sheared.

2) Sodium - my soil science professor used to tell us that the easy way to remember 'Na' stands for 'sodium' on the periodic table is because sodium does NAsty things to soil. Chemically, it makes the individual clay particles repel from each other - making them all equidistant from each other means there is no longer any pore space.

Don't use table salt in your garden - no matter what pinterest tells you about how well it kills the weeds organically. (You might be able to get away with this in a sandy soil in limited amounts, but I especially do not recommend it on a clay soil.) Should your child ever go dump a container of Morton table salt in a section of your yard, calcium (generally in the form of gypsum) reverses the effect that sodium has on soil structure.

3) Shearing - have you ever filled in a hole with wood putty or caulk? You know, when you scrape a shapeless blob of the stuff over the hole to fill it in? Well, clay particles are so tiny, this can essentially happen with your pore space. The really unfortunate thing is, it can happen when you are digging with your shovel.

You are better off digging with a pitchfork in clay soil if you can manage it. Again, avoid working on the soil when it is really wet.

My Process for Planting an Apple Tree
1) Grab your pitchfork. (And don't go after your quarrelsome neighbor.)

2) Check the soil moisture level. You don't want it to be sopping wet, nor do you want it to be bone dry. If you work when the soil has a small amount of moisture, it will break apart easily into crumbles. Then those crumbles tend to stick around. (These conditions are ideal any time you're going to work with clay soil - especially if you're ever going to rototill it.) You can actually test this to see if it will crumble in your hand.

3) Dig a Hole. Make it just as deep as the container, but at least twice as wide. The same depth because the soil will settle and you don't want the crown of the plant to sink down lower than it should be. Ideally, you want the sides to slope in gradually.

It is OK if the soil doesn't look super-smooth on the sides of your hole. Having irregular, choppy, rough edges is actually better for the plant. When a root hits a material that is significantly harder than what it's been growing in, it figures it's hit a rock and turns to move along the rock face until it finds a) softer soil or b) a crevice to jam itself into to work its way between two rocks. The soil you eventually dump back in will probably be a bit softer/looser than it was before. If the hole is too regular and smooth and round, your roots may never venture out into the surrounding soil.

When I planted an apple tree the other day, I piled all of the soil I dug out to the downward side of the hole. You know how you're often advised to make a ring around the tree to help keep the water in when you first water it? Well, the 'ring' isn't needed on the top side of the hill because water always flows downhill. Adding soil on the uphill side isn't benign either - piling soil on the uphill side would essentially divert runoff coming from further up the hill away from my tree. That's not something I want, so I focus on making a mini-berm on the bottom side. I actually want the mini berm to be a little higher than where the trunk will meet the soil so the water will sink in around the trunk. Also, making the area completely level may allow the water to run off.

When I plant, I don't dig a simple hole. I add trenches leading in toward where my tree will be planted. On a hill, this means I add two channels going in a V shape up the hill. The idea is that any runoff further up will hit the channel and then start flowing down toward my new fruit tree. On level ground, I spread them out in about 5 directions like spokes. The bottom of each channel slopes down toward the rootball pit. This creates an area of looser (and damper) soil for my tree roots to spread out into, encouraging them to venture out into the broader landscape. Afterall, the further the roots go out, the better they will be able to capture moisture during our droughty summers.

4) Add Organic Matter. Almost any problem in the soil can be solved by adding organic matter. Organic mater helps bind soil particles into aggregates, improving drainage. At the same time, it can hold 6x its weight in water, so it improves and moderates the moisture level in the soil. It also holds onto nutrients and encourages microbial life in the soil, which works to release nutrients from both the organic matter and the mineral portions of the soil.

Now, I don't make the planting hole too rich. If you do that, your tree will concentrate its roots where the 'good stuff'' is and that can interfere with it's ability to spread out into a wider area, which can hurt during periods of low rainfall. Instead, I mix the organic matter with the existing soil.

In the case of our local clay, this often means I grab a chunk of dislodged sod and whack it repeatedly against the backside curve of the pitchfork, or the ground, to dislodge small chunks of soil. If the soil isn't super-wet, the soil breaks off into crumbles and then I can actually mix the organic material throughout the hole with my hands as easily as any pre-packaged soil mixture.

The organic matter I mix in may be a bag of planting medium I pick up from the store, compost, or even some of the bark-based planting medium that came in the pot of the plant I'm installing. In fact, I usually try to get as much of the plant's current potting soil mixed into the natural soil of its final home as possible. This helps to give the plant a transition from one soil environment to another. I also amend the trenches I have going out from the main hole.

5) Gently Tease Apart the Rootball.  If you are planting a bare-root tree, this isn't an issue. But if your tree comes in a pot, then you want to make sure you don't have any girdling roots (roots that circle around the tree relatively close to the trunk - they will restrict the tree's ability to send out roots in the future and may even strangle the tree over time if they are really close to the trunk).

Plants are often re-potted several times in the nursery before they come home with you. Sometimes you may pull out a rootball from a pot and think, 'OK, I don't see any roots creeping around the sides', and then think you're fine. However, what happens if the roots became overcrowded when the plant was stuffed in a pot two sizes smaller? They might still be overcrowded two or three inches in. This is why I try to gently tease apart the rootball as much as possible. There's usually at least one root (the taproot) that wants to be longer than the container will allow and has been forced to circle the pot a fair distance. I try very very hard to avoid breaking any roots during this process, but if the pot is overcrowded, I will allow myself to break through some of the smallest, hairlike roots.

6) Place Your Tree.  I try to gently tease the roots so that they will spread out in different directions. If there are really, really long roots that would need to circle around in my planting hole, I try to direct them so that they are heading out along one of my trenches. (Another reason for doing a trench: you have a place to put those extra-long roots without having to dig up half your yard for a gigantic, wide hole.)

The crown of the tree is where the trunk meets the root system. You will usually see a difference in the color of the bark at the crown. On fruit trees, it is often NOT the widest part of the trunk. Fruit trees are almost always grafted. As a part of knitting the two trees together, the tree forms callous tissue, which can make the graft union more swollen. Evidence of a pruning cut will often appear near the graft as well (but not always depending on the grafting method). Trees are almost always grafted 3 inches to 5 above the crown because if the grafted tree has a chance to send down roots, it will overcome the dwarfing influence of the grafted rootstock.

You want the crown to be right at the final soil level. You also want to check to see if your tree is upright. (The tree can adapt to being a bit crooked, but it might drive you nuts.)  Step down lightly on the soil around the trunk to make sure the tree has a firm contact with the new soil.

7) Stake if the tree is in a windy location or looks like it is going to tip.  If it looks like the tree will stake upright without needing additional help, I do not stake. Small whips often do not need staking. Larger specimens with lots of branches up top are more at risk.

If I do stake, I remember to remove any supports within a year. I also try to avoid staking immediately next to the trunk because it can do weird things to the trunk when the stake is close enough to consistently deprive light to one side of the trunk .

8) Water.  One long soak is better than 5 short sprinkles. The apple tree I just planted is still dormant, so it doesn't need as much water. But I make sure that any new tree gets supplemental water for the first summer. I have ordered a few WaterGators off of ebay to help provide a consistent supply of water to new trees while they establish during the hot summer months.

One word of caution: I have seen blackwidows take up residence under the WaterGators because it's dark and it's moist, and that moisture attracts prey (other bugs). This is especially true with the junior watergators, which have a lower, wider profile and a darker color (the brown absorbs more heat than the green bags). By the way, you may be horrified to know that Stafford has not one, but two different species of black widow: one with just the red hourglass on the bottom and one with the red hourglass underneath AND red spots on the top of its swollen abdomen. I've found three of the black ones and one of the red-and-black ones since I moved here 3 years ago.

9) Mulch is good for your tree. It helps keep the soil (and therefore the roots) cool, keeps the water from evaporating as quickly, and protects the soil from erosion/force of heavy raindrops. If you use an organic mulch, it also absorbs water and adds nutrients/organic mater to the soil. For the apple I planted yesterday, I actually mulched it with straw because that is what I readily had on hand. I will mulch it with shredded hardwood later.

When it comes to mulch, trees like t-shirts, not turtlenecks. You want to keep the mulch 2-3 inches away from the trunk of the tree. This helps the crown to stay healthy. It also helps keep mice from chewing the outer layer of bark off the side of the tree, killing it via girdling.


For Further Information on Caring for Apple Trees
I recommend taking a look at what the Extension Service at Virginia Tech has put together about caring for apple trees: https://pubs.ext.vt.edu/422/422-023/422-023_pdf.pdf