Which Bonsai Pot Should I Choose
Here I show you the things you need to know when choosing between a shallow bonsai pot or a deeper pot for your bonsai tree. I present the aesthetic know-how accumulated from many experienced bonsai artists over the last five decades. I explain the horticultural effects that will impact your bonsai if you use a shallow pot, a deeper pot, or a large grow pot for pre-bonsai development.
Which do you choose for your bonsai a shallower pot or a deeper pot stick around and i’ll help you decide [Music] today i’m going to repot these two boxwoods but this video isn’t about repotting it’s about what pot i’m going to choose what i’m going to talk about today is the horticultural aspect of how deep the pot is and what happens to the roots depending on how shallow or deep the pot is
think of the pot as a bit like a picture frame it should emphasize the tree’s beauty but it should not outshine the tree so let’s consider a refined bonsai which means you’ve already developed the trunk and the primary branching structure now the classical view the pot height should be approximately equal to the diameter of the trunk [Music] and that view has been expressed by many important bonsai artists over the last several decades and it really does look right but there are obvious exceptions to the rule like cascades and forest plantings
in any case these are not hard and fast rules the way it looks to you is infinitely more important or in other words beauty is in the eye of the beholder [Music] so let’s consider the idea of visual mass which is the perceived bulk density of a tree or of a trunk or a branch or an entire group planting david de gru in his excellent book principles of bonsai design says that the visual mass of the pot should be about one quarter of the visual mass of the tree and a quick reminder we’re talking about refined bonsai here i’ll get onto developing trees in a minute now let’s park the aesthetic considerations to one side and instead think about the fact that we’re growing a real living tree in a small container now here’s a quiz in these three pots with soil inside them with drainage holes underneath
which part do you think holds the most water per granule of soil in other words which one takes longest before the roots get dry [Music] to answer that let’s fill them up with water and look at how the soil retains the water in every absorbent material you get what’s called a perched water table which completely saturates a layer of soil and won’t drain out the drainage holes it’s held there by the balance between gravity pulling it down and the capillary action in the soil trying to wick up the water now here it comes the most important point the perched water table is only caused by the soil’s water retention and not by the pot this means that the perched water table is the same height regardless of the depth of the pots
so if you use the same type of soil then the shallower pot is going to be a lot more waterlogged than the deeper pot [Music] now let’s consider what all this means for your roots of course the perched water table does evaporate off or get absorbed into the roots but clearly just after you’ve watered the roots in the shallow pot are going to be much more waterlogged for a while now there isn’t a right or wrong answer here for pot depth but if you do choose a shallow pot it’s good advice to mound up the soil a bit and plant your tree a little higher because you don’t want those roots to be sitting permanently in waterlogged soil starved of oxygen and here’s another tip for cooler climates or colder times of year after watering just tip that shallow pot up a bit and watch how the water drains out the lower end that’ll get more oxygen to the soil and to the roots
and for additional hints now we’ll take a quick look at what happens in deeper pots so i’ve said a few times before if you want to thicken up the trunk of your bonsai you could either put it in a bigger deeper pot or even plant it in the ground but let’s look at for example a deeper pot like this all you’re doing is giving the roots more space to grow into and leaving it for a couple of years maybe three years and that’s how you get it to grow bigger by just not trimming the roots not pruning the roots but when you have a bigger container it may seem counterintuitive but the top half is going to get much drier than if you have it in a shallower container so naturally the roots are going to be encouraged to grow downwards deeper so really it’s just a development phase for a bonsai it’s not suitable for a long-term storage container for for a bonsai unless that is you want to develop a cascade or a semi-cascade which needs typically a deeper pot so the topsoil on taller pots always dries quicker but that doesn’t necessarily mean you have to water it straight away the important thing is to keep the soil moist but not continually waterlogged you can easily test the soil a couple of inches under the surface using a pointy stick
here you can see there is still some moisture but not much so i will water it now because it’s getting quite hot out already beware with shallow pots because if the soil dries on the surface in those you really do need to water them straight away and when you’re watering a tree in any pot just make sure the water does come out the drainage hole at the bottom partly so you know you’ve watered enough but mainly so you know your soil and pot are draining freely [Music] so back to my box with bonsai i’ve chosen this shallow oval pot but i guess you knew that already from the thumbnail of this video . Check it out
Expert Tips to Growing Better Bonsai