POTS & CONTAINERS TIPS
🪴 It is very common for many new to rooting to root their cuttings in plastic party cups. They’re cheap, easy to obtain, and don’t require any investment in something you may not use again. The pros are understandable! However, I do not recommend rooting in cups. It can be done, but often has problems at the up-potting stage because they frequently require up-potting before the cutting has stabilized. They also are short and so limit how much of the cutting you can bury. The more nodes you have buried, the more area you have for roots to develop, which can lead to a stronger plant.
As an alternative, I recommend quart deli containers, 2 liter soda/water bottles, or 1 gallon nursery containers over cups if treepots are not available. These allow plenty of time for the cutting to grow sufficiently and to stabilize before requiring an up-pot. Be sure to make an adequate amount of drainage holes in the bottom before using. Soldering irons can be great for this or carefully heating a large nail grasped by pliers can work as well. A drill bit can also be used, and can go through several stacked together at once, but these also can cause the containers to split if not careful.
🪴 I prefer to root in treepots because they are tall enough to bury the bulk of the cutting while easily keeping the bottom of the cutting out of the perched water table, which is a location rot can happen if the cutting is too low in the pot.
🪴 I also prefer treepots because you do not need to tease out or score the roots before up-potting even when very rootbound. If rooting in a normal pot, gently tease the roots out at the bottom when up-potting for the first time so that they grow out and not continue to circle in the same pattern which will affect growth.
🪴 You will know your cutting has rooted in an opaque container based on the amount of top growth. An unrooted cutting can have a little leaf growth, but it will be minor in comparison to a rooted cutting and will start to fail if the cutting has not rooted. So if it is actively growing, it has rooted.
Resources:
My favorite treepots: Stuewe & Sons 4x9.5 Mini Treepot
Mini-Treepotsâ„¢ & Trays Kit - TRAY6 WITH TP49 KIT - Stuewe & Sons
Also available here: https://www.greenhousemegastore.com/products/treepots
ROOTING MIX TIPS
🪨 Compost, manure, worm castings are good for plants, right? Yes, for plants. I do not use any organic matter in my rooting mixes though. Organic matter wants to break down, that is how it works and how it feeds your plants. By its nature, it encourages bacterial & fungal growth in potting mix, which is fantastic for the outdoors and for a growing plant. But this composting action also encourages anaerobic bacteria to develop in your rooting medium which can cause your cutting to rot. It can be very water retentive as well, which can be smothering to new roots. Organic matter can also harbor insect eggs and seems to bring on fungus gnats in indoor rooting setups. I save the organic matter for later after rooting has been successful and once outdoors.
🪨 If you are into pH, 5.0 to 6.5 has been recommended as being better for rooting mixes. It is not something I typically worry about myself, but both peat and coco coir mixes typically happen to fall nicely into this range. This range reportedly helps to prevent mold growth. But be aware that other ingredients can raise pH such as perlite and certain mineral components.
🪨 Aeration in rooting mixes is very important for rooting success and to prevent rot. There can be a fine balance between having too much aeration and not enough depending on how you grow and your climate. If you are someone who tends to overwater or you live in a very humid environment, the more aeration the better.
Aerating materials allow you to have more water present without worry. The less aerating materials you have in your mix, the more you need to worry about how much water you are using because water fills in the few air gaps available in a fine mix. I prefer medium sized aerating materials for a rooting mix, larger sizes for potting mix. Smaller sized particles are not suitable for cuttings and are for seed starting instead. Aeration is your friend for rooting and growing and is a must for root health.
More detail on rooting mix formulation linked here.