Hi, I’d like to grow an oak tree next month for my daughter’s first birthday (her name means Oak tree in Irish). We live in a condo facing southwest, and eventually would like to move to a house. Is it possible to grow an oak tree sapling in a pot outdoors for a few years before planting in the ground? And if so, what conditions would be most favourable in terms of soil, sunlight, fertilizer, etc?
Thank you for contacting the Toronto Master Gardeners for your thoughtful question on growing an Oak tree sapling in a container for perhaps a few years.
It is certainly a nice sentiment to acquire the oak tree now, the likelihood of having it survive multiple winters on (not to mention summers) in a balcony setting is very small.
I could provide you with all sorts of recommendations and references, but I will outline several key challenges;
1) Outside containers are subject to thawing and refreezing, often leading to winter-kill. Nurseries can deal with this problem by burying containers in protective mulches. Other methods for mitigating freeze/thaw in a residential balcony setting can be to wrap containers with styrofoam , bubble wrap or other air barriers (which will moderate the thawing and freezing action).
2) Another consideration is the size of the container used to house a young tree which is destined for transplant. On one hand the larger the container the more difficult it will be handle and transplant, while the smaller the container the least likely the chances for survival, as it will dry out faster, freeze and thaw more readily, and restrict proper root growth. Most oaks grow at a rate of 1 – 2 feet per year. A 6 foot oak trees will require at least a 30 gallon container (approx 30″ in height and 25″ at top circumference). Your best chance of success will be to start with a small seedling, to allow for growth and size projection.
3) Balcony environments can be challenging for growing small trees in that they can be very windy and drying, have extremes in sun exposure / shade or scorching sun reflection.
If you think you can mitigate and manage these variables, then here are a few care instruction;
- Your southwest exposure is fine, as long as you can avoid sun scorch from reflected light off of glass. Also try and protect container from too much direct sun heating as well.
- Prefers dry to medium moisture, acidic soil in full sun. Prefers fertile, sandy, finely-textured soils with good drainage ( Ensure that container has drainage holes and drainage material at bottom of container).
- For fertilizing, only use a 20-20-20 fertilizer sparingly…… (once a year).
- Use protective wrap in winter time as mentioned above.
- Watering practices depend on drying conditions.
The answer depends on a few variables which I will turn into assumptions. These related variables are for how long, and ultimately how large do we plan on it getting. Obviously the larger the tree gets before you transplant it, the greater the challenges and the risks to survival.
So assuming that we are planning on growing an oak tree which may get to be a maximum of say 6-8 feet, then we must plan on having a container that is worthy of housing the root structure necessary to support the tree, and also consider your ability to successfully transplant this.
Please see link below which lists many different oak species and their preferred habitat, growth habits and characteristics, etc. This may help you select the proper species and care.
Good luck !