If you buy your starter plants from the nursery or grocery store, they will probably come in very small plastic pots and you want to transplant the herbs to a 6” or even 12” pot right away so they have enough room to grow.
If you are using a terracotta pot, then be sure to soak it overnight in water as mentioned here, failure to do so may result in the pot soaking up all the moisture and damage to your plant.
How to transplanting herbs?
Transplanting the actual herb is very easy. The first thing you want to do is make sure your potting soil has some moisture to it. You don’t want it to be soggy – when you squish a ball of it together in your hand you want it to clump together and not fall apart on its own, but you don’t want any drips of water to wring out of it.
Line the bottom of the pot with a layer of the potting soil mix deep enough so that when you place the herb into the pot, the crown of it is level with where you will fill the soil up to. Most pots have a little lip there, so you can experiment with placing the herbs (while still in its original pot) inside the new pot and see if it comes up to the lip, if not add more soil – if it is higher take some away.
Remove the herb from it’s container
Once you have the perfect amount of soil in the new pot, remove the herb gently from it’s container by squeezing the sides, turning the container upside down and gently coaxing the plant out by grabbing the base of the crown and working it from side to side to break it free. Most plants will come out quite easily with very little tugging.
Take a good look at the root ball when you have it out, you want nice white roots that hold the soil loosely. If the root ball is compacted, loosen up the roots with your fingers.
Place the plant into the middle of the new container on top of the soil you added to the bottom. Put more soil around the sides until the soil reaches the crown of the root. Press the top of the root ball down into the soil and gently press the sides of the soil as well. You want the plant to be well seated but you don’t want the soil to be compacted too much.
Finally, water the plant slowly until water starts to drain out the hole in the bottom.
How to prepare soil for herbs?
Herbs need soil which will ventilate the air and drain the water efficiently, this is particularly crucial during winter months, so be sure to add perlite, coarse sand, or peat moss to your soil mixes. Mix your potting soil using a ratio of two parts soil to one part coarse sand; this will help keep the soil dry. Unless you are planting Mint or other herbs that grow well in moist soil, most herbs people grow indoors like Basil, Oregano and Parsley do not grow well in moist soils.
How do you balance pH in soil?
Be sure to use a neutral and balanced sterilized compost based mix, with pH levels between 6 and 7, soils that have a high acid content will produce burnt out, tasteless herbs.
Do not use the soil that you take from your outdoor garden for any indoor herb gardens. The garden soil drainage abilities outside will be much different when planted inside a container, and most likely will not be adequate for your indoor herb garden. Not only that but the soil is not sterilized like the soil you buy in bags at the garden center so you may be introducing pests, larva or other things into your indoor garden that you do not want.
Quality indoor herb garden soils are readily available at any plant or gardening store, just keep in mind which herbs you want to grow and whether they require moisture controlled soils or if they thrive in moist soils.
Do I need to fertilize the soil?
Fertilizing the soil once the plants are out of the seeding stage is recommended but not required, especially if you purchased an indoor soil mix with nutrient release. If you want to feed the soil yourself, you can boost the soil with liquid fertilizers or organic fish emulsion feedings when the plants are actively growing, this can help produce a boost to the growing cycle and create tastier herbs.
You may also want to keep in mind if you are trying to grow your indoor herbs organically that some prepackaged indoor herb soil mixes and fertilizers are not organic. You can always check the internet for organic fertilizers if you are having trouble finding any at your local store. Using organic plant protection will also help keep your soil free of any insects.