Espoma | Seed Starting 101: How to Start Seeds Successfully

Seed starting is upon us in the gardening world! There is no better way to connect with the food we eat than by growing it ourselves. Starting edible plants from seed can be intimidating, but we’re here to break it down and answer all your burning questions.

This blog is inspired by Episode 114 of Bloom and Grow Radio–where host Maria Failla interviewed Joe Lamp’l–the Joe behind The joe gardener Show.

Before we dive into the how of seed starting, let’s understand the why.

Why Start Your Garden from Seed?

In our world of instant gratification, what’s better than starting your gardening season way sooner than most gardeners?! When you start seeds indoors, you get your hands in the dirt and get a jump on the growing season. And what a rewarding feeling it is to start your plants from seed, and enjoy the journey of bringing them from seed to plate.

If you love your edibles, decide what you want to eat and which varieties you want. Don’t leave it up to what’s available at the garden center. Think about how much you can choose when you start from seed: flavor, varieties, and the stories behind different heirlooms. You can really expand your food choices when you get to pick exactly what you grow.

Another great reason to start your own seeds is to make sure you’re growing the right kind of plant for your needs. Do you absolutely love tomatoes, but only have a small balcony to grow them? Look for microdwarf tomato varieties that only grow about 1-2 feet tall! If you have a short growing season, you’d also want to make sure you choose “early” or “short season” plant varieties.

Starting from seed offers us the ability to be in control of the varieties we grow, plan in advance, and save lots of money in the long run. Speaking of starting seeds on a budget…

How to Get Your Seed Starting Setup for Under $100

Your seed starting setup can be super budget-friendly if you take the time to look at the components. For under a hundred dollars, you can put together everything you need! Let’s break down the materials, costs, alternatives, and conditions you need for seed starting.

Seed Starting Mix

To start, you need a good seed starting mix. It’s called a “mix,” because there’s really no soil in it. It’s made of natural ingredients like peat moss, vermiculite, and perlite. A bag of seed starting mix is going to cost between $5-$10.

Espoma Organics takes the guesswork out of your selection by providing their high quality seed starting mix.

Seed Starting Trays

With one bag of seed starting mix, you can fill about two seed starting trays, which is your next material needed. Seed starting trays can give you anywhere between 18 to 72 cells to sow your seeds. You can get two trays for about $10.

Look for seed starting trays with cells about 3.5 inches or smaller. In a traditional seed starting tray, cells are deep so seedling roots have more room to grow down. About 4 weeks from germination you’ll have to transplant your seedlings into a larger individual pot, AKA “potting up”.

Best Grow Lights for Seed Starting

Next is a grow light. Grow lights are where you could spend a lot of money in your seed starting setup, but if you’re on a budget, there is nothing wrong with buying a LED or fluorescent shop light for $20. You can get your seeds sprouted and ready for planting outside in good condition with a very inexpensive shop light. Will it be as good as a seedling that’s under a more expensive light? Maybe not, but all you’re really trying to do is rear those seedlings to the point that they are ready to go outside. Once they get outside, mother nature knows what to do and so does that seedling.

What are Heat Mats for Seed Starting important?

Heat mats are seed starting game changers. Heat mats raise the soil temperature, which helps your seeds sprout faster. Seeds have an ideal range of soil temperature in which they sprout the best, and can be anywhere from 65 to 85 degrees Fahrenheit. Seed mats will cost you between $15 and $35, depending on whether you get a thermostat attached.

Once most of your seeds have germinated, remove them from the heat mats. If you leave your seedlings on heat too long, they can start to become leggy.

Humidity Dome for Germination

You’ll also want a humidity dome. It’s a clear plastic top that you put over the seed tray to hold the moisture in the soil until the seed germinates. If you don’t have a cover on your tray, the moisture won’t stay in the soil and the seed is not as likely to germinate. For two humidity domes, you’ll probably pay about $6. You can also use plastic wrap and lay it over the top to hold in moisture for your seedlings.

A key point to remember with humidity domes: once your seeds germinate, remove the humidity dome so seedlings get enough oxygen. Air flow brings us to the next material needed.

Small Fan for Seed Starting

Last but not least, a fan. You can get a cheap clip-on fan for $15. Fans are important because once the seed germinates, you need air movement across that soil surface. Air movement reduces the chance of a fungal disease called damping off, which can kill your seedlings. Fans also simulate wind, making the stems sturdier and ready for outdoor conditions.

Total Seed Starting Materials Cost

Here’s the cost breakdown to get your seed starting setup for less than $100:

Bag of seed starting mix: $10

2 seed starting trays: $10

Shop light: $20

Heat mat: $15 – $35

Humidity dome: $6

Clip-on fan: $15

TOTAL: $81 – $96

All about Seeds: Where to Buy Them, Expiration Dates, & Non-GMOs

It’s important to find a good seed company. Here are some tips when you’re searching:

Look for companies that have been around for a while with a good reputation.
- Do they have good customer service?
- Are their staff knowledgeable about their seeds?
Find local or regional seed companies that grow their seeds close to home. Some seed companies can outsource their seeds from overseas from a huge commercial supplier. It’s important to know where your seeds are grown.
When you grow seeds adapted to your area, plants have a much better success rate. The more you grow those seeds and save them, the more adapted they’ll become to your specific microclimate too!

Seed Expiration Dates

Seed packets will show the day that the seed was packed. Assuming you have leftover seeds and you keep them in a cool, dark, dry place, they will last anywhere from as little as one year to many years, depending on the seed.

How do you know when a seed is still good or if it’s gone bad? Do a germination test! Before you plant your seeds, put about 10 seeds in a damp paper towel in a plastic bag. Check the moisture daily and after about 10-14 days, your seeds will either have sprouted or not. If 7 out of 10 sprouted, your viability is about 70%. Depending on your viability you can either plant extra or compost unusable seeds.

What are Non-GMO Seeds?

GMO stands for Genetically Modified Organism. Many seed companies have jumped on the bandwagon saying all of their seeds are “certified non-GMO.” There actually aren’t any GMO gardening seeds available for home gardeners. None of the seeds you purchase will ever be GMO seeds. GMO seeds are present in the commercial agriculture industry, but it’s expensive to produce a GMO seed and it’s not anything that we’re going to even be able to buy. So if a company is touting non-GMO seeds, that’s true, they are. But so are everyone else’s.

The Best Time to Start Your Seeds

The most important date you need to know is the last day that you are potentially going to have frost. This is called your frost-free date in Spring. You can find yours by Googling “last frost date” in your area. Once you have that date, then you work backwards to about 6-8 weeks. That’s when you’ll be sowing most of your seeds.

You want to time your seed starting so you give your seeds about 6-8 weeks of growing time indoors. By the end of the 6-8 weeks, seedlings will have grown to a sturdy size and are then ready to grow outdoors. If you choose a good seed company, there should be lots of information about this on the back of the seed packet.

If you start your seeds too early, you risk your plants getting too big and outgrowing their space. They’re going to be looking for resources that you probably can’t provide indoors, like more light, nutrition in the soil, and space to grow. The longer your seedlings are confined indoors without the right environment, the more stressed they become. Timing when you plant your seeds is crucial to the seed starting process.

Let’s Get Planting!

Now that you’ve got your seed starting setup and timing down, how do you get your seeds in the soil?

First, look at the information on your seed packet. It will typically have all that important seed starting information you need, including how many weeks to start indoors, days to maturity, and growth patterns.

Make sure your seed starting mix is pre-moistened, like a damp sponge. Most seeds don’t need light to germinate, but they don’t need to be planted very deeply either. Once you have your seeds in, sprinkle a little bit of extra seed starting mix on top. Spray the tops of the soil gently with water so you don’t move the seeds around too much.

When your seeds are planted, place your humidity dome on top, put your tray on your heat mat, and turn your lights on. Your seedlings are going to sprout in a matter of days to a week, maybe two weeks at most. Once your seeds germinate, remove your humidity dome and turn on your fan. From there, you’re just ensuring that the soil stays moist.

The first leaves that come up are called seed leaves, or cotyledons. In a few weeks, your plants will grow new “true” leaves. Once those new true leaves emerge, you can start to add small amounts of supplemental fertilizer.

Your job over the next 4-5 weeks will be monitoring plant growth and making sure everything looks good. Keeping the lights at the proper distance above the tops of the seedlings is also key–not too close, not too far away.

The Final Step: How to Harden Off Your Plants

Hardening off is about 7 to 10 days of transitioning your seedlings slowly to outdoor conditions. You slowly increase the tender, new leaves’ exposure to sun and wind over about two weeks. Make sure outdoor temperatures are above 45 degrees fahrenheit with no inclement weather during this period, and bring plants indoors every evening.

Here is a rough schedule to follow: