When the planting gets to the point where root congestion allows you to lift the root/soil mass from the pot intact, the plant will benefit from a repot. A repot is more involved than simply potting up in that it includes bare-rooting, root pruning, and a change of soil; whereas potting up is essentially lifting the congested (rootbound) root/soil mass from one pot into a slightly larger pot and filling the space between the pot walls and the root/soil mass with potting medium. When you pot up, most of the limitations associated with root congestion follow the plant to the new pot, but all stress associated with root congestion is relieved during a proper repotting session.

.... best not to water on a schedule. Water on an 'as needed' basis, using a wooden "tell" you can easily make in minutes from a wooden dowel rod. See below.

Don't forget fertilizing, it's very important. If you're watering correctly, so you're flushing the soil as you water, fertilizing about every 3rd or 4th time you water in summer and every 4th or 5th time in winter is about right. You can keep track of how many times you water by dropping a marble/ button. bottle cap in the pot at every watering. When it's time to drop in the 3rd/ 4th/ 5th object, depending on how often you decide it's appropriate to fertilize, fertilize, pick up the objects, start the cycle over.

Using a 'tell'

Over-watering saps vitality and is one of the most common plant assassins, so learning to avoid it is worth the small effort. Plants make and store their own energy source – photosynthate - (sugar/glucose). Functioning roots need energy to drive their metabolic processes, and in order to get it, they use oxygen to burn (oxidize) their food. From this, we can see that terrestrial plants need plenty of air (oxygen) in the soil to drive root function. Many off-the-shelf soils hold too much water and not enough air to support the kind of root health most growers would like to see; and, a healthy root system is a prerequisite to a healthy plant.

Watering in small sips leads to avoid over-watering leads to a residual build-up of dissolved solids (salts) in the soil from tapwater and fertilizer solutions, which limits a plant's ability to absorb water – so watering in sips simply moves us to the other horn of a dilemma. It creates another problem that requires resolution. Better, would be to simply adopt a soil that drains well enough to allow watering to beyond the saturation point, so we're flushing the soil of accumulating dissolved solids whenever we water; this, w/o the plant being forced to pay a tax in the form of reduced vitality, due to prolong periods of soil saturation. Sometimes, though, that's not a course we can immediately steer, which makes controlling how often we water a very important factor.

In many cases, we can judge whether or not a planting needs watering by hefting the pot. This is especially true if the pot is made from light material, like plastic, but doesn't work (as) well when the pot is made from heavier material, like clay, or when the size/weight of the pot precludes grabbing it with one hand to judge its weight and gauge the need for water.

Fingers stuck an inch or two into the soil work ok for shallow pots, but not for deep pots. Deep pots might have 3 or more inches of soil that feels totally dry, while the lower several inches of the soil is 100% saturated. Obviously, the lack of oxygen in the root zone situation can wreak havoc with root health and cause the loss of a very notable measure of your plant's potential. Inexpensive watering meters don't even measure moisture levels, they measure electrical conductivity. Clean the tip and insert it into a cup of distilled water and witness the fact it reads 'DRY'.

One of the most reliable methods of checking a planting's need for water is using a 'tell'. You can use a bamboo skewer in a pinch, but a wooden dowel rod of about 5/16” (75-85mm) would work better. They usually come 48” (120cm) long and can usually be cut in half and serve as a pair. Sharpen all 4 ends in a pencil sharpener and slightly blunt the tip so it's about the diameter of the head on a straight pin. Push the wooden tell deep into the soil. Don't worry, it won't harm the root system. If the plant is quite root-bound, you might need to try several places until you find one where you can push it all the way to the pot's bottom. Leave it a few seconds, then withdraw it and inspect the tip for moisture. For most plantings, withhold water until the tell comes out dry or nearly so. If you see signs of wilting, adjust the interval between waterings so drought stress isn't a recurring issue.

Al

i would look at this link.. to see what the future holds for my plant ...

https://duckduckgo.com/?q=calathea+Pinstripe+mature&t=ffab&iar=images&iax=images&ia=images

but regardless.. you only go one pot size up.. and repot every few years .... you will probably fail.. if you plant a tiny plant in a huge pot.. because someday that babe might fit that pot.. dont ask me why.. but it just doesnt work ...

put your fingers over the top of the media.. with the stalks between your fingers.. and try to shake or gently pull the plant out of the pot... when all you see is roots ont eh sides and bottom.. then you will start seeing roots out the drain holes.. this plant would need repotting.. and perhaps some sever root pruning.. if extreme .. you really dont want to get to this point ... you could probably flip to the video side of this link?

https://duckduckgo.com/?t=ffab&q=root+bound+plant&iax=images&ia=images

as al probably noted.. it should be watered when it needs water.. not come random schedule... after you water the next time... just lift the pot.. and try to tell its weight ... and then.. wait your week.. and note how much lighter it is .... the weight difference is the water i the pot .... when your media fails.. it will not hold that water .. and then you will need to repot .. might be years from now ...

ken

btw.. if that is a fluorescent light.. and its for the plants.. you might want to start a new post.. on the proper use of such ... it looks too far away from the plants in this pic.... ken

Fluorecent light is not used, it gets natural light