Repotting Mistakes | What to do and NOT to do when repotting so your plants don't die
Ready? Set? Repot! Wait. No. Don't do that. Put down that pot. Take your hands off that scoop. Here's what to do before, during and after repotting, which ideally starts the day before...
But why bother with this extra care? Because repotting for your plant, is like major surgery is for us. Getting in our best health before surgery, allowing the right conditions for recovery, and the right care after surgery, is all just as important for us for a speedy recovery without complications, as it is for our plants. But when it comes to plants we call that 'transplant stress' and what you do before, during and after repotting can make all the difference.
Is repotting the same as potting up?
But before we jump in. Keep in mind repotting and potting up are not technically the same. Potting up can be done all year-round, causes minimal disruption for roots, and has faster recovery. Repotting usually involves the removal of old potting mix, and is best done before or after the growing season (early Spring and late Autumn are ideal) as it's far more disruptive for roots.
Potting up is much less drastic for a plant as it involves simply shifting a plant - old potting mix and all - up a pot size, adding a little new potting into the bottom and around the sides with little to no damage or disruption to the roots. I'm personally happy to pot up any time of year, although still tend to avoid the middle of winter unless necessary (to be fair, when I have space on my heat mat, then I'll happily pot up and repot all year round).
Here's what's in this guide. Click to jump to each section, or scroll down to read start to finish...
What could go wrong with repotting?
What supplies do you need when repotting?
How long can you store potting mix? Is old potting mix safe to use?
Step one: Prepare your plant before repotting (bath time!)
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What could go wrong when repotting?
Repotting, done well, can result in a happier, healthier plant that bounces back quickly. When repotting goes wrong, you could be dealing with root rot or even plant death. Both are avoidable. The 'best of the worst' is simply that plants stop growing for a while after repotting. But done right, they will quickly bounce back and grow better than before.
Symptoms of transplant stress from repotting include yellowing leaves, leaf drop, wilting even when watered, no new growth or root damage. These extra two steps below will help you give your plants the best chances of a speedy recovery, with no complications.
Quick disclaimer: As always with plants, a lot of 'best practice' is trial and error based on what works the best for the most people. This is what works best for my jungle which averages around 100 indoor plants - a mix of my own collection and plants I propagate and grow for sale, combined with some handy tips and tricks from my mentors.
Supplies
Before you start, you ideally want to grab all of the following...
- Potting mix (whether store-bought or DIY). My current fave is Bio Leaf or Wildvine.
- A soil scoop (a big salad spoon does the trick too).
- The pot you're potting up into (I'm loving clear pots at the moment).
- A mask (avoid breathing in soil dust, silt or particles).
- Gloves (and always wash your hands after handling potting mix too).
- Seaweed or a root growth booster - optional but HIGHLY recommended (a few options below).
- Fertiliser - optional but recommended (my faves below).
- A potting mat - also totally optional, but wow, what a game-changer for something so simple, I love mine.
- Water (made into a nutrient solution, more about that coming up).
Is your potting mix still okay to use?
If you've just got yourself a fresh bag of potting mix, skip this section and go to Step 1: Prepare your plant below.
Before you literally dig in, keep in mind old potting mix might not be ok to use. You won't always find an official 'expiry date' or 'best before' stamped on the bag, but you should aim to store unopened potting mix no longer than about 6 months in ideal conditions, stored sealed in an air-tight bag or container somewhere cool and dry.
However, the more natural and organic your mix is, the shorter the storage. Closed or opened, it's best to use up mixes with organic ingredients within 30 days. As long as it's kept dry, most rock and mineral substrates (perlite, pumice, leca, pon, vermiculite and similar), can be stored long-term and used as and when needed. They don't expire or 'go bad'.
Over time, potting mix can decompose and compact, reducing the air space roots need. old potting mix can also become hydrophobic (where it repels water), and minerals salts can increase, which can burn roots (once potted up, regular watering flushes out excess salts - one reason a rinse of older soil is recommended before potting up).
What's in your mix definitely changes how long you can store it without it degrading also. The more yummy organic matter is in there, the happier your plant will be, however the sooner you should use up the bag for maximum goodies for your plant.
Bugs and pests (good and bad) are also more likely to set-up home in potting mix if stored for a while. Fungus Gnats in particular love stored soil if moist and warm, as well as fungi itself. You'll sometimes find small white fluffy balls (I think of them as baby fungus), or even mushrooms, growing in old stored potting mix. If stored potting mix gets warm and wet, that can also be an ideal breeding ground for bacteria. Store your soil somewhere dry at room temperature indoors to keep it fresher, longer.
Step 1: Prepare your plant for repotting - with a bath!
Ideally the 4 steps are as follows (however most people just do step 3 which is why health problems after potting up are so common).
- Prep your plant
- Prep your soil
- Repot
- Recovery
When should you prep plants before repotting?
Before repotting, make up some nutrient solution and give your plant a nutrient bath a day or two before you plan to repot. I try to time this with when the plant's due to be watered anyway. You can make your own nutrient solution combo, but for my guys, I use a mix of fertiliser and seaweed. More about these products, how much I use, and other options coming up.
Why give plants a nutrient bath before you repot?
As well as helping to loosen old potting mix attached to the roots, a nutrient bath also helps soften the roots and make them more bendy and less likely to break or be damaged during repotting. The nutrients themselves also give plants a boost of essential nutrients, and help the roots recover better from the stress and shock of repotting.
What goes in the nutrient bath?
Grab yourself your usual fertiliser plus either seaweed or a growth-booster that is formulated to support roots. The product guide below gives you a few options that I've tried and recommend. This is what you'll use to make the nutrient solution ready for bath time. I use my usual fertiliser, plus something targeted to help the roots specifically.
How to give plants a nutrient bath before repotting
It's bath time! Mix your fertiliser with water. Add either a growth booster, root booster or seaweed (a few options below), and you've made your nutrient solution. Then give your plant a good soak! There are two popular methods:
The bath method is pretty much what it sounds like, and is really just a variation on bottom watering but using a nutrient solution. Pop your plant in an outer container, pot and all (no need to remove or disturb the plant at this stage).
Fill the outer container up with nutrient solution until the water's about 3/4 of the way up the inner pot. Leave the plant to soak for up to 60 minutes maximum, or until the top of the substrate is wet (I find 15 to 30 minutes is usually plenty but if your substrate has low water retention - like bark - longer may be needed to make sure it's fully saturated). Remove the plant and let it drain. Done!
Or you can do a top water drench. Thoroughly top water your plant with nutrient solution until the substrate is fully saturated (it may take at least two pour throughs). I'll usually water heavily until water freely pours out the drainage holes, wait 5 minutes, then repeat again. Give the plant time to drain, and you're done.
What nutrients to use
There are a few options here so you may have what you need in your plant cupboard already. One popular option is fertiliser + seaweed. Another is fertiliser + a root booster. You'll often see seaweed recommended for use before and after repotting because it's known to reduce transplant stress for plants. If you check the label, you may find your fertiliser or root booster already includes seaweed, so may not need to buy it separately.
But no, because your nutrient bath needs to tick a few boxes for how it benefits your plants both before and after repotting, there isn't one product to rule them all (yet! no doubt some clever company will create one just for repotting). I've included a few options below with the goal of using what you already have rather than buying new. I'm a big fan of products being multi-purpose - and saving those pennies for more plants!
FERTILISERS
Since roots will be soaking in it for a while, if you go for the bottom method for your nutrient bath, one option is a reduced-salt fertiliser (it's the mineral salts in fertiliser than can cause fertiliser burn, which can damage roots). Some fertilisers are lower salt than others.
One of my favourite fertilisers to reduce the risk of fertiliser burn is the Growth Technology (GT) range. I like that their formulas have no urea, chlorides or sodium (chlorides in particular are one of the highest salt index ingredients in most fertilisers). I use their Foliage Focus formula at 3mls per 1 litre to make up my repotting nutrient solution.
Or, if you DON'T have seaweed, but don't want to buy extra products, another top pick has to be Plant Runner Indoor Plant Food as it's high in nitrogen for roots and leaves, but also includes seaweed. I use Plant Runner at 1ml per 1 litre.
For my international plant buddies, as far as fertiliser goes, I haven't found GT Foliage Focus or Plant Runner on Amazon sorry, but you can get Dyna-Gro Foliage Pro on Amazon (after all, it's an American brand). They are going through a re-brand at the moment, so it may be called Superthrive Foliage-Pro by the time you read this.
+ SEAWEED
For seaweed for my overseas readers, a friend who is a professional grower based in Florida recommends Bloom City Seaweed and Kelp Fertilizer but she did want me to pass on to ignore the dose on the bottle and dilute it to 0.5ml per gallon for potted plants so a little goes a long way.
My plants all get a light seaweed feed once a month, and fertiliser every time I water, so I keep fertiliser and seaweed on hand anyway, meaning I don't need to buy anything special for repotting. For seaweed (if you're in New Zealand), my fave is BioPower Organic Seaweed at 2 grams seaweed flake per 1 litre of water.
+ ROOT BOOSTER
You might have also seen root boosters around. Although the ingredients differ, root boosters are great to have on hand for both before and after repotting, since avoiding or at least minimising root damage is your #1 concern when repotting. I prefer any product I have to be multi-purpose as I don't repot all the time, and both of these root boosters below tick that box too.
One is called GT CCS (Growth Technology Clonex Clone Solution), and no, it's not Clonex rooting gel, but is made by the same company. For CCS I use 5mls per 1 litre of water. If you have it already - as CCS is also used for root growth when propagating - keep in mind it replaces fertiliser in your nutrient solution. That's important to know because most root boosters are only additives, not complete fertilisers like CCS is.
Leaving what may possibly be the best till last, is a new product I started trialling a couple of months ago that has really impressed me. This is a root booster that does not replace the need for fertiliser - but it also includes seaweed as well as natural plant growth hormones. It helps roots recover faster after repotting and gets growth happening again quicker also. Also made by GT, it's called Rootzone and I use it at 1ml per 1 litre water added to fertiliser in my nutrient solution.
For me? Right now my pre-repot go-to for a good root soak is a combo of GT Foliage Focus or Plant Runner for my fertiliser, plus GT Rootzone for the seaweed and root booster in one.
Step 2: Prepare your potting mix
Whatever combination of ingredients you buy or DIY for your potting mix, give it a good shake or mix up first. Multi-ingredient potting mixes (like Bioleaf or Wildvine), can settle in the bag when stored or during transport, with the fine stuff usually ending up at the bottom.
Pour out how much potting mix you'll need into a container, and give it a water or spray until lightly moist if it's on the dry side. Water helps 'stick' or bind together all those different ingredients, so once mixed you get an even distribution throughout the pot.
You also want to mix it well so you don't accidentally end up with a perched water table which reduces drainage. That's the same reason you should never add a drainage layer. Now pot up as you normally do...
Step 3: Repot
For me, this part usually means sliding the plant out of its old pot, and gently removing the old substrate from around the roots (I like using my squeeze water bottle for that or just running them under the tap).
Whatever method you use, avoid damaging or breaking any roots if you can. Shaking the plant or pulling substrate off the roots with your hands can take the roots or delicate root hairs along with it, so I prefer to take it gently and use water to do the job, not force.
If you find the rootball is dense and compacted, maybe it became rootbound before you got around to repotting, you will likely need to loosen that root-ball up gently, so the roots venture out into the new potting mix once repotted.
That soak you did a day or two earlier will have helped soften and loosen roots to make this whole part of the process much easier with less root damage caused. Sometimes you just have to get rough with those roots, and may break off or damage a few roots in the process. That's where step 4 (recovery) comes in.
...we interrupt our normal broadcasting for a Public Service Announcement
TIP #1 If you hate repotting as much as I do (the mess, the fuss), get yourself a potting mat. This is a must-have for me when repotting. Make all the mess you want! Repot anywhere you want (in front of the TV gets my vote). Repot indoors in winter. No more wasting soil. For my international plant friends, Owl Focus do them in lots of sizes and colours. You guys can also get my favourite iridescent potting mats.
The sides snap together, keeping mess contained. You can also un-snap one corner and simply tip out excess soil back into the bag to use later and avoid waste, then roll it up for next time. Potting mats come in a few sizes but I much prefer the 75cm x 75cm size myself (that ends up about 65 x 65cm once the corners are snapped together).
TIP #2 My other repotting tip might seem weird, but it's NOT to make your own mix. I absolutely will do that when I have the time, not to mention the spare storage room for all the ingredients (and the energy to bother). But these days the custom blends you can get are seriously fantastic and thoroughly tested by other plant hobbyists much fussier than me. My favourite is the custom blends by Bio Leaf. I'm also loving pure Fern Fibre lately too, especially for my Hoyas.
Something else I love about both the Bioleaf and Fern Fibre, is minimal mess and easy clean-up. My old go-to of indoor potting mix along with a blend of Perlite and other bits and bobs, was just mess central. You should still wear gloves and a mask though like any potting mix. Health first!
Step 4: Recovery care for your plant after repotting
It feels like all the hard work's done now - and to be fair, the physical stuff is done and dusted - but how well you care for your plants after repotting makes a big difference in how fast they recover and start growing again.
It can be quite normal for plants to temporarily stop growing after repotting, especially if you went up a lot bigger in pot size. What you want to try to avoid is transplant stress, such as yellowing, wilting, dropping leaves, roots that don't recover, root rot or even plant death. No thank you!
Right after repotting
Remember the new potting mix will be relatively dry straight after repotting. Give your newly potted plant another really good drench or soak with the same nutrient solution you made up for step 1. You can either go for the bath method and bottom water, or thoroughly top water.
I prefer to give plants a bath (bottom water) as step one, a day or two before I repot, then I like to thoroughly top water drench after repotting, as top watering also helps flush out excess dirt and silt from the new substrate. Up to you.
For the month following repotting
You can just return to your usual water and fertiliser routine after repotting, provided your plant's recovering fine, but I like to keep giving those roots the VIP treatment to help the plant recover. I'm currently using GT CCS root fertiliser plus GT Rootzone (that's the one that includes seaweed too), to temporarily replace my usual routine for the first month after repotting to help roots recover and get growing.
WHERE OH WHERE?
Advice about where to put a plant after repotting varies, but in warmer months I simply return the plant to the same conditions it was in before repotting, to minimise the amount of change it's dealing with.
Some advise keeping plants warmer after repotting, some in a shaded area. Either way, direct sun after repotting is best avoided for at least a week or two, even if the plant used to get direct sun on the regular. When repotting in winter or when the temperature's colder than usual, I always pop mine on a heat mat also, or you can choose somewhere warm and bright, out of drafts or the path of the air con or heater.
I'm not convinced there are big differences between brands when it comes to heat pads (also called seedling mats), but I use the Inkbird brand myself. If you're international you have a brand of heat mats called Vivosun which is really popular too.
Congratulations!
Phew! That covered a lot. Well done for making it to the end. It does seems a lot at first, but becomes second nature after the first couple of times you follow this method. Plus I find it weirdly comforting giving my plants this much love, knowing I'm doing everything I can for them to come out the other end after repotting, happier and healthier than before. At the end of the day, the key difference with this method is that nutrient bath 1 to 2 days before, then again after you repot, along with keeping warmth in mind for roots to recover.