NO plant likes root congestion. There are times when root congestion might serve the grower because it has an effect on the plant the grower likes, but that isn't a clear indicator the plant will like it. Tight roots cause stress and all sorts of physiological problems for all plants. It reduces growth, branch extension, and leaf size. It limits vitality and caused the shedding of older leaves proximal (closer to the trunk) to growing branch tips (apices). If anyone tells you that a particular plant prefers to be root bound w/o explaining what they really mean is some growers like to maintain a particular plant in root bound conditions, they're wrong. If "some plants" really did prefer root bound conditions, Mother Nature would surely have arranged the plant's genetics so it grew tight little masses of roots right under the stem ..... but we know there are no plants that naturally occur that way. That said, your plant probably isn't in any immediate danger that pertains to root congestion. You're better to suffer the limitations the plant is now growing under for a while in exchange for a more opportune time to repot, which for you would be next June. Plants have natural rhythms, during which their energy levels wax and wane. For major work, like repotting (which includes root pruning), it's best to ask the plant to endure the added stress of repotting or rejuvenation pruning when its energy levels are at peak - not now when they are at or approaching their lowest levels of the entire growth cycle. If you haven't read it, the link below should be very helpful. If you are wondering about repotting and how to maintain trees in containers for the long haul, this link offers lots of guidance. Al Here is a link that might be useful: Lots more info

I forgot to mention, I just read in an old post that pale yellow growth could be caused by growing in cold weather, maybe this is the same thing and I shouldn't worry until summer?

I strongly disagree. A full repot is actually REQUIRED if your plant is to be given full opportunity to function as close as possible to its genetic potential. The effects of repotting are short lived, so even though a repotted plant can be expected to sulk for a week or two before it resumes a much higher growth rate and level of vitality than its potted up counterpart, by the end of summer the repotted plant will have far surpassed the plant potted up in growth, and it will be healthier - all else being equal. This is F benjamina in the process of being repotted. It's been growing in a nursery can for a few years, so needs an extreme root reduction and flattening of the root system over time to allow it to fit in a shallow pot. ^^^ You can see by the large pile of soil under the plant that a good deal of soil/perimeter roots have already been removed and the solid mat that was the bottom 1/3-1/2 of the root mass has been removed and discarded.^^^ After removing most of the soil, I'll remove the large roots that serve almost no purpose (other than plumbing and anchorage). Under this mass, as you'll be able to see from the next image, are some VERY thick roots that I'll remove with very little thought about the process. ^^^ End result. In 1 or 2 more repots, the large roots under the trunk will be 'gnawed' off with a special tool designed for that purpose. Eventually, all roots will be radiating horizontally from the widest point of the trunk flare. Please note: I'm not suggesting that everyone should adopt root pruning to this extreme as a habit. I don't - you shouldn't. It just serves as a good illustration of how much root work a healthy tree is able to tolerate. After performing several thousand repots, I've gained a sense of what a tree will handle. For tropicals, it's based on how well they over-wintered indoors and their current level of vitality and growth rate when I repot in June. For temperate deciduous trees, the determination re how much root mass can be removed is based on their condition in late fall as they approached dormancy. I can say though, that when I do repot, the volume of roots removed would always make someone uninitiated to the practice unnecessarily fear for the tree's well-being. Al

Fennel - Reposted per your request. I hope you can see it. If not, send another message and I'll send it direct.I think you're on the right track in your thinking, but for the sake of full disclosure: - It's best to repot it in early summer. Technically not quite true. Summer STARTS Jun 21. In most locales, repotting should be done by then, but you can repot even i8n northern US States into Early Aug with good results. - It needs fast draining soil no matter what and likes low nutrient content like in the gritty mix. There ARE work-arounds that allow you to use soils that would be wholly unsatisfactory w/o the work-around. Ballast, wicks, and several other tricks can be used to limit how much 'excess' water a pot can hold. - I have to keep the fine roots wet during repotting. True - It shouldn't be fertilized again until it starts new growth. True - It's good to trim the roots 30% or more. I'd limit my first foray into root pruning to removing 1/3-1/2 of the roots, total ...... and I'd concentrate on large roots that are problematic for one reason or another and not connected to the base of the trunk. However, I still have some newbie questions. - I live in zone 10b (Malibu, USA). Should I still wait until June to repot it? Can you manage to hold off until Memorial Day? That's when I would do it if I lived in Malibu. - The soil. This is my biggest question. I understand gritty mix would give my tree the most potential but I highly dislike the idea of completely depending on plant food and watering as often as I've seen gritty mix users say they have to water (every 3-4 days even). Is there perhaps a different ratio or set of ingredients I could mix to give the soil only a little less potential but a lot more leniency in those areas? I wish there was a list somewhere of the detailed benefits and pitfalls of different common soil ingredients. If you're going to do things to the gritty mix that eliminate the reasons you would go to the extra effort to begin with, push it to the back of your mind. It simply doesn't make sense from the perspective of economics or effort to make an expensive soil you might as easily have made with less effort and reduced outlay. I'd be thinking of something like the 5:1:1 mix, which is based on a high % of coarse ingredients, but still holds more water than the gritty mix. - Root pruning. Again, I'm new to plant care. How do you tell which roots are are healthy and which are sickly or dead beneath the soil line? You'll know. Healthy = white or tan, not black, dark brown/ slimy. Am I correct that I should prune the large roots without a lot of feeder roots? Yes What should I look for beyond that? Roots that point back toward the center of the root mass, roots growing straight up or down, hooked/ encircling/ girdling roots. I've seen people straight up hack inches off the rootball. Is that much removal and abrasion very beneficial to the tree or can I just gently separate the roots and cut off obvious problem ones? I alway start by hacking a significant fraction of the lower root mass off - often as much as 75%, but that's not meant as a suggestion to you. How much you can safely remove will come with experience. I was uneasy enough with root pruning as it was and then found some even more disconcerting posts about how foliage may need pruning also to a level the new roots can support. I definitely don't want to prune my roots to a level near enough to likely need leaf pruning. It's still a short tree and every leaf is healthy. FWIW - a ficus will alway benefit from pruning when you repot if you concentrate your pruning efforts at the top of the tree, which ALWAYS robs the bottom of the tree of its due, in terms of food and energy. I can say, without question, that if you continue to progress in your proficiency at growing trees in containers, at some point you will be regularly pruning at least the top of almost all apically dominant trees when you repot, for more than 1 reason. - Keeping the roots wet. How do I do this? Should I keep a light shower on them? Should I dunk them in a bucket of water every minute? Could someone please suggest an exact method and interval to do this right? I normally work over a tub of water and dunk the roots as often as necessary to keep them wet at all times. When it's cool/ humid/ shady, that might be every 2-3 minutes. Hot/ windy/ sunny = every 30 seconds or so. You can also use a hose & pressure nozzle to 'blast' soil off roots. This ^^^ fits on the hose end. Adding a shut-off helps save water. - Watering. Should I water it right after repotting? Yes Does the tree need to be kept in extra moist or extra dry soil before or after the report? The fraction of soil that holds the roots needs to be damp - not wet or dry - damp. If your soil is appropriate, you can easily water a couple of times each day to ensure roots get enough moisture w/o suffering from soil saturation. Also, I've seen mention of people soaking their ingredients/soil before mixing/potting into it but I don't understand it. What's that part about? Some soils, when they get dry, become hydrophobic (water repellent). To correct, make mud from about 1/3 of the soil you'll need for the repot, then mix in the dry soil. Do this well before you start the repot or transplant. By the time you need the soil, diffusion of moisture in the soil will have 'broken' any tendency toward hydrophobia. - Fertilizing. Should I fertilise some time before the repot? Give it more strength somehow? Yes. Fertilize appropriately right up until the day you repot, and resume as soon as you see new growth being pushed. I bought some Foliage Pro 9-3-6 recently but haven't been fertilising at all since I got the tree; just been giving it filtered water. You should fertilize regularly all year long - varying the dosage and/or the intervals between applications in response to what part of the growth cycle your tree is in. I often fertilize at more than 2.5x the recommended maximum dose when cultural conditions support that practice. You can learn more about fertilizing containerized plants if you click me. - Pot size. I read these trees enjoy small pots False. Read this. and can even be repotted into the same pot after root pruning True but I think mine is pushing it. It's over 2.5 feet tall in a 6-inch pot. I'm definitely going 8-inch minimum—but would it be better to go for a 10-inch? How large a container ‘can’ or ‘should’ be, depends on the relationship between the mass of the plant material you are working with and your choice of soil. 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 a basic understanding about the relationship we will look at, which logically determines appropriate container size. It's often parroted that you should only move up one container size when "potting-up". The reasoning is, that when potting up to a container more than one size larger, the soil will remain wet too long and cause root rot issues, but it is the size/mass of the plant material you are working with, and the physical properties of the soil you choose that determines both the upper & lower limits of appropriate container size - not a formulaic upward progression of container sizes. In many cases, after root pruning a plant, it may even be appropriate to step down a container size or two, but as you will see, that also depends on the physical properties of the soil you choose. It's not uncommon for me, after a repot/root-pruning to pot in containers as small as 1/5 the size as that which the plant had been growing in prior to the work. Plants grown in ‘slow’ (slow-draining/water-retentive) 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 before root issues beyond impaired root function/metabolism become a limiting factor. We know that the anaerobic (airless) conditions that accompany soggy soils quickly kill fine roots and impair root function/metabolism. We also know smaller soil volumes and the root constriction that accompany them cause plants to both extend branches 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 your 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 per se, but rather, they rebel at being potted into very large containers with a soil that is too slow and water-retentive. This is a key point. We know that there is an inverse relationship between soil particle size and the height of the perched water table (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 (fully saturated). So, if you aim for a soil (like the gritty mix) composed primarily of particles larger than 1/16", there is no upper limit to container size, other than what you can practically manage. The lower size limit will be determined by the soil volume's ability to allow room for roots to ’run’ and to furnish water enough to sustain the plant between irrigations. Bearing heavily on this ability is the ratio of fine roots to coarse roots. It takes a minimum amount of fine rootage to support the canopy under high water demand. If the container is full of large roots, there may not be room for a sufficient volume of the fine roots that do all the water/nutrient delivery work and the coarse roots, too. You can grow a very large plant in a very small container if the roots have been well managed and the lion's share of the rootage is fine. You can also grow very small plants, even seedlings, in very large containers if the soil is fast (free-draining and well-aerated) enough that the soil holds no, or very little perched water. I have just offered clear illustration why the oft repeated advice to ‘resist potting up more than one pot size at a time’, only applies when using heavy, water-retentive soils. Those using well-aerated soils are not bound by the same restrictions. As the ht and volume of the perched water table are reduced, the potential for negative effects associated with over-potting are diminished in a direct relationship with the reduction - up to the point at which the soil holds no (or an insignificant amount) of perched water and over-potting pretty much becomes a non-issue. Al