Having the right supplies can make or break the success of your seedlings when starting seeds indoors. Let’s go over the basic supplies required. Check out my Indoor Seed Starting Guide once you have gathered all of your supplies!
- Seed trays or pots
- Seed starting soil
- Labels
- Spray bottle
- Grow lights or a sunny window
- Heat mat
- Fan
Trays and pots
When choosing seed starting trays, it’s important to consider factors such as drainage, size, and material. Whatever tray you choose, ensure that it is clean, sterile, and provides adequate drainage to prevent drowning your seeds and fungal growth.
Plastic trays
These are the most common choice and can be used year after year if cared for properly. They come in various sizes so you can choose what size will work best for your space and the amount of seeds you are starting. They can be filled with small plastic starter pots or jiffy pellets.
Biodegradable trays or pots
These may be the more eco-friendly option than plastic but you will need to replace them every year. They can be planted directly into the ground which can help prevent transplant shock. I have found that these work best with seedlings that don’t need much grow time indoors as they don’t hold up as well.
Repurposed containers
Many household containers can be repurposed as seed starting trays, such as egg cartons, yogurt cups, milk cartons, or plastic food containers. These can be a cost-effective option, but it’s important to ensure that they have drainage holes and are clean and sterilized before use.
Soil
Seed starting soil is specifically designed to provide the ideal growing conditions for seeds. It is typically lighter and more porous than regular potting soil, which allows for better drainage and root development. You can find seed starting soil at your local garden center or online. Another easy option is to use Jiffy pellets. They are dry, compact discs that you soak in water to create little growing pods. You can even mix together your own seed starting soil with the recipe below.
Seed Starting Soil
- 1 part peat moss or coconut coir
- 1 part vermiculite
- 1 part perlite
- 1/2 part compost or worm castings
- 1/2 part finely screened garden soil (optional)
Labels
Make sure to label your seed trays or pots with the name of the plant and the date you planted the seeds. Labeling will help you keep track of what you’ve planted and when. Many seedlings look similar so if you forget to label, you may have a hard time determining what is what. You can purchase plant labels online or at most garden centers. Instead of purchasing, I like to make my own by cutting yogurt containers into strips. These garden markers come in handy as the ink doesn’t bleed or fade from the sunshine and water.
Water
At the time of initial seed sowing, I suggest misting the soil surface to keep it moist during the germination period. However, once the seeds have germinated, you will want to water from the bottom by adding water directly to the seed tray. Always use room temperature water when watering indoor seedlings, as cold water can shock the plants and damage their roots.
Light
Light is essential for seedling growth, and it’s recommended to use grow lights or LED shop lights to provide the necessary light spectrum for the seedlings. To ensure optimal growth, seedlings need 12-16 hours of light per day, and using a timer can help maintain a consistent lighting schedule. If you don’t have access to artificial lighting, a south-facing window that receives ample sunlight can be an alternative option.
Heat mat
Most seeds need warmth to germinate, and using a heat mat underneath your seedlings can help provide the optimal temperature for germination. A heat mat is particularly helpful in colder environments, and it can be removed once the seedlings have germinated. Using a heat mat can result in faster germination and an improved germination rate. They can be found at most garden centers and online. I use this one from Vivosun.
Fan
Finally, good airflow is essential for preventing fungal growth on the soil surface. Use a fan to provide good air circulation around your seedlings. This will help prevent damping off, a common fungal disease that affects seedlings. The fan can also assist in hardening off the plants and prepare them for being planted outdoors.
Happy Growing!
