I purchased a one gallon size Bougainvillea to grow into a large planter (approx 22"). Can I put it right in and fill it up with potting mix or should I pot up one size at a time?
Regardless of what the plant is, you can put it right into it's 'final' container from the get go if the growing mix drains well.
Where people get into problems is with mixes that hold too much water. In such a case using a 'just big enough' container works better as it will hold less water due to lower potting mix volume and the plant has a better chance of using the water before it becomes a problem.
If you think about it, in nature nobody goes around potting up plants. They grow where they grow and if conditions are favorable they thrive and if not they don't.
If drainage is adequate any plant can go right into the container it will spend the rest of it's life in, no potting up necessary.
Same thing he said:
It depends .....
From another post: "How large a container needs to be, or CAN be, and how much soil a planting needs/will tolerate before drainage & saturation is an issue depends on the 3-way relationship between plant mass, container size, and soil type. We often concern ourselves with "over-potting" (using a container that is too large), but "over-potting" is a term that arises from a lack of basic knowledge about the 3-way relationship noted, which should logically determine appropriate container size(s).
It's often parroted that you should only move up one size in containers when "potting-up". The reasoning is the soil will remain wet too long and cause root rot issues, but it is the size/mass of the material and soil type/composition that determines both the upper & lower limits of appropriate container size - not consecutive volume progression.
Plants grown in slow soils need to be grown in containers with smaller soil volumes so that the plant can use water quickly, allowing air to return to the soil. This (smaller soil volumes) and the root constriction that accompanies it will cause plants to extend and gain o/a mass much more slowly - a bane if rapid growth is the goal - a boon if growth restriction and a compact plant are what you have you sights set on.
Conversely, rampant growth can be had by growing in very large containers and in very fast soils where frequent watering and fertilizing is required - so it's not that plants rebel at being potted into very large containers or volumes of soil per se, but rather, they rebel at being potted into very large containers with a large volume of soil that is too slow and water-retentive.
We know that there is an inverse relationship between soil particle size and the height of the PWT in containers. As particle size increases, the height of the PWT decreases, until at about a particle size of just under 1/8 inch, soils will no longer hold perched water. If there is no perched water, the soil is ALWAYS well aerated, even when the soil is at container capacity (saturated).
So, if you aim for a soil composed primarily of particles >1/16", there is no upper limit to container size. The lower size limit will be determined by the soil volume's ability to furnish water enough to sustain the plant between irrigations."
You can grow a very small plant in a very large container if the soil holds little or no perched water (no saturated soil).
Thanks for the detailed explanations. I purchased Scotts organic potting mix. Will this be sufficient or should I add perlite to it? How can I tell if the soil is good?
Bougainvillea can grow into huge plants. My neighbor's was even growing up his Eucalyptus tree and covered his whole fence. Would a container really be suitable?
How can I tell if the soil is good?
By reading this post :)
"Bougainvillea can grow into huge plants. My neighbor's was even growing up his Eucalyptus tree and covered his whole fence. Would a container really be suitable?"
I live in Fl...yes, they can be grown in containers, they tolerate heavy pruning...I used to live in a house that had a huge bougainvillea growing against the fence of my house. I lived there for 12 years, and once a year I would prune it to about two feet tall(got as tall as 7-8 ft) and it would come back...nice and full.
Now I only grow them in containers(Al's mix of course)...I prefer the "bonsai" style...small and short. I prune mine once a year to maintain its small size...