Starting seeds indoors isn’t difficult and is the best way to take advantage of the wide variety of vegetables, flowers, and herbs available from seed companies. Plus, starting your own seeds produces a lot of plants for little money and lets you control the growing conditions. And that means the most robust seedlings for your garden. But what equipment do you need for indoor seed starting? Discover the best seed starting set up and 8 essential items I use to grow thousands of seedlings each spring. 

The best seed starting set up

What do you really need to start seeds? Do new seed starters need to invest in a grow light? Or plug flats? Or soil blockers? Absolutely not! You can start seeds in a sunny window in recycled containers like egg cartons, yogurt tubs, or coffee pods. However, if you grow a lot of seeds for your garden, it’s nice to have a dedicated seed-starting area and all the equipment to ensure healthy plant growth. You can also buy seed starting kits that come with most of the below supplies including a growlight, seedling trays, and cell packs or peat pellets. Here’s what you need for the best seed starting set up:

8 essentials for the best seed starting set up

1) Light source

The most important element of successful seed starting is light. Too little light and seedlings grow tall and thin, eventually flopping over. It can be difficult to find a window that provides enough light for healthy plant growth, especially if you’re starting a lot of seeds. Plus if you’re starting slow growing seeds, like onions or lisianthus, that need at least 10 to 12 weeks of indoor growth, there won’t be enough mid-winter light for them to grow strong and stocky. 

To get around the issue of low light, gardeners turn to grow lights. In fact, the best seed starting set up requires grow lights because it allows you to control the amount of light. There are many types of grow lights you can use with LED and fluorescent (often just shop lights) the most popular. I’ve used both successfully for decades, but if given the choice, I’d buy an LED fixture as they have a very long lifespan, use less energy, and don’t produce excess heat that can affect seedling growth.

Depending on your needs, indoor space, and the amount of seedlings you wish to grow, you can buy tabletop LED grow lights or grow light stands with multiple shelves.

2) Containers

When starting seeds indoors you’ll need something to sow the seeds in. There are a lot of options for containers including cell packs, plug trays, plastic pots, recycled items like egg cartons or toilet paper rolls, peat pellets, and soil blocks. Below is a chart that shares the benefits and drawbacks of each of these container types.

3) Soil

Using the best soil gives your seedlings a strong start and there are several products that work for seed-starting. 

• All-purpose potting soil – These soils are made from a mixture of peat moss, coconut coir, perlite, vermiculite, compost, manure, and fertilizers. 
• Seed-starting mix – These are generally a bit more expensive than all-purpose potting soil, but are made up of a finer grade of materials with a light, fluffy texture. Most brands also sterilize their seed-starting mixtures to prevent fungal issues like damping-off. Sterilizing also eliminates pests like fungus gnats. 
• DIY potting mix – It’s not difficult to make your own potting mix for seed starting. It allows you to control the ingredients and quality, as well as sterilize it if you like. That said, buying individual ingredients can get expensive. However if you’d like to try making your own, check out our DIY seed starting mix recipes.

Because I’m a budget minded gardener and start a lot of seeds, I buy compressed bales of all-purpose potting mix. It does the job well and because I buy it by the bale, it’s much cheaper than buying a lot of smaller bags. 

4) Humidity dome

The next essential item for the best starting set up is a humidity dome. A humidity dome maintains high humidity to prevent the growing mix from drying out during germination. If the soil dries out, the seeds may die before they break through the soil surface. You can buy regular humidity domes, high domes, or use a piece of plastic wrap overtop containers and flats.

Once germination has taken place and you see green emerging from the potting mix, remove the humidity dome. Leaving it on too long can damage the tender seedlings as well as keep moisture levels too high prompting surface mold. 

5) Watering container

Keeping the growing mix evenly damp – not wet – is a vital step in starting seeds indoors. To do this most gardeners use a watering can or a hand mister. A mister is great for the early stages when the seeds are germinating and the growing mix doesn’t dry out very quickly. However, once the seedlings are growing well and starting to size up, they need to be watered more often. This is where a watering can comes in handy.

There are many types, styles, and sizes of watering cans available and mine has both a rose attachment and a spout attachment. The rose attachment delivers a gentle flow of water to tender, just-sprouted seedlings while the spout attachment provides a stronger flow of water as the plants grow. Learn more by reading our guide on how often to water seedlings.

6) Labels and markers

If you’re sowing more than one type of seed, you need to label your containers. Trust me, all tomato varieties look very similar as seedlings and it’s impossible to tell them apart! I use white plastic labels and a waterproof marker to label my containers. It’s quick, easy, and keeps me organized. 

7) Seeds

It’s fairly obvious that in order to start seeds indoors you’re going to need seed packets. You can order them from your favorite seed catalogs, pick them up from a nursery, or buy them from local companies at a seed event like Seedy Saturday. Most seeds can be stored in a cool, dry spot for several years. However, if you’re not sure how old your seeds are and whether they’re still viable, do this simple paper towel test. Good seed can be planted, while ones that don’t sprout can be tossed in the compost.

8) Fan

A fan might seem like an odd bit of equipment for seed starting, but trust me, this is a must-have! A small oscillating fan provides a light breeze to your seed starting area. This accomplishes two things: 1) it keeps air moving to reduce the risk of fungal issues like damping off and 2) it strengths the stems of your seedlings, making them more robust and better able to cope when moved outdoors. 

Extras for the best seed starting set up

I didn’t include the below items in my best seed starting set up, but are helpful if you have the space and budget.

• Heat mat – Often called a seedling heat mat, this item is a flat, waterproof mat that goes beneath your seed trays. It raises the soil temp by 10 to 20 degrees F (6 to 11 degrees C). This is super useful when starting warm season seeds like hot peppers, tomatoes, basil, and many flowers. A seedling heat mat boosts germination rates so more seeds sprout and it also speeds up germination. A win-win for seed starters!
• Timer – As a general rule of thumb, I leave my grow lights turned on for 16 to 18 hours a day but sometimes I do forget to turn them on or off. To to make my life easier, I use a timer to do this job. It’s a nice thing to add to your seed starting supplies. 
• Fertilizer – Once my seedlings have two sets of true leaves, I start to feed them with a diluted liquid organic fertilizer. This ensures they have the nutrients they need for strong root and shoot development. 

Now that we’ve learned more about the best seed starting setup, check out these articles on growing from seed:

• The best LED grow lights for indoor gardening
• Soil blocking: A better way to start seeds
• How to grow tomatoes from seeds