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If you’re a beginner to growing vegetables, I can understand any skepticism or concerns you may have about your abilities. Believe me, I was once in the same boat. However, this article will serve as a painless guide to starting vegetable seeds, so that you can grow your own vegetables with confidence.
My mom used to love gardening when I was younger. Thus, I grew up having a lot of plants indoors or helping her tend to flowers or vegetables outdoors. As a result, I thought I had quite a green thumb with successfully keeping indoor plants alive later as an adult.
However, my confidence later waned after moving into a house that had dramatically less natural light. I had very little luck with indoor plants and even felt I had a “black thumb” at that point!
Thus, when I decided to give vegetable gardening a try, I was skeptical from my prior bad luck with plants. Much to my surprise, my vegetables all grew well! Starting vegetable seeds and then growing them into vegetables was not as difficult as I feared.
This article will also get you past that initial, perhaps intimidating hump of starting vegetable seeds, so that you can be on your way to growing your own vegetables.
Starting Vegetable Seeds Indoors Versus Outdoors
I prefer starting vegetables seeds indoors, because your vegetables will be most vulnerable in their early seedling days. Having a consistent, controlled environment will help ensure that your seedlings grow strong and can transition to growing outdoors, if the latter is your ultimate objective.
Thus, regardless of the climate you live in, you can cultivate a hospitable environment inside for your seeds to germinate and grow healthily as seedling.
For these reasons, my article will focus on starting vegetable seeds inside in pots. I will also discuss variables to help you decide whether to keep your vegetables in pots indefinitely or to plant them outside. Your final planting medium should dictate the types of vegetables you plant.
The Best Time for Starting Vegetable Seeds
If you plan to transfer or transplant your vegetables outdoors at any point, you must figure out your plant hardiness zone. Here is a USDA map, where you can click on your state to find your particular area’s plant hardiness zone.
Your plant hardiness zone can tell you what types of plants usually thrive in your climate, along with suggested planting times. Keep in mind that you may have to adjust for other factors in optimizing vegetable growth, such as soil composition, direct sunlight, and weather patterns.
When in doubt, start with suggested planting time for your particular plant hardiness zone and then start your vegetable seeds indoors 4-6 weeks prior. For instance, since we live in Zone 9a, we start seeds inside in September for our fall/winter garden.
Factors for Choosing Vegetable Seeds
If your climate and yard permit, growing vegetables outdoors in- ground or in a large garden bed is ideal for soil depth, pollination, and air circulation. However, some vegetables, and particularly herbs, are fine indoors with the right conditions.
Aside from climate, three main factors you should consider on whether to grow certain vegetables are below:
- Soil depth and spacing requirements
- Pollination requirements
- Sunlight requirements
Let’s discuss each factor further below, so you’ll have a better understanding of your vegetables’ needs.
Soil Depth and Spacing Requirements
Vegetables need enough soil depth for their roots to spread. Unfortunately, different vegetables require different soil depths. Some vegetables are fine with shallow soil depths (i.e. up to 12 inches deep), while others require greater depths.
If you plan to grow vegetables in containers only, then you should stick with vegetables requiring shallow soil depths or plan to get really large pots.
For vegetables that grow long roots (e.g. carrots, radishes), consider sowing the seeds directly into your large container or garden bed, since their roots are usually more sensitive to transplanting later.
You also need to consider how much spacing each plant needs away from others. If you don’t give your vegetables enough spacing, roots can become crammed and unable to access sufficient nutrients from the soil. Also, taller plants may block shorter plants from accessing sufficient sunlight.
Generally speaking, green, leafy vegetables like herbs and lettuces may do better in smaller mediums than other vegetables.
Pollination occurs when sources like bees or wind transfer pollen from the plant’s male organ (anther) to the female organ (flower stigma). Plants require pollination to produce vegetables or fruits.
Some vegetable plants are self-pollinating (e.g. lettuce, beans, peppers, tomatoes), so don’t need external sources for pollination. These plants would be fine growing indoors indefinitely. Otherwise, if you don’t have self-pollinating plants, you can try to pollinate the plants yourself.
Before seeds germinate (i.e. sprout), sunlight isn’t too important. However, one sprouts emerge through the soil, you should ensure the seedlings get adequate light.
Plants use sunlight for photosynthesis, i.e. converting carbon dioxide and water into food for the plant. Thus, without adequate light, you vegetables won’t grow strong or properly.
We learned the hard way with our first attempt at starting vegetable seeds simply placing seedlings by a sunny window wasn’t enough. The seedlings were leggy, meaning they grew taller and quicker than normal, trying to reach more sunlight. Because they grew too fast, the stalks were weak and unable to hold themselves up straight.
If you think about it, when plants grow outside, the sun is shining down on them. Thus, limiting their sunlight to one side through a window will make them grow towards that light. Thus, they will grow crooked.
Shining a full-spectrum LED light (T8 or T12; 6000 Kelvin) down on your seedlings will ensure they get strong, even lighting. You don’t need a “grow light” at this stage, but just a regular LED light. We bought our 4-foot LED lights from a local hardware store.
If you keep your vegetables growing indoors beyond the seedling stage, then you should invest in a good grow light to mimic the sunlight your plants need.
Pro Tip: If you are completely new to gardening, I would recommend starting with herb seeds like basil, which is usually pretty hardy and easy to grow. It’s also a versatile herb to have on hand for raw dishes like caprese or salads, or cooked!
Supplies Needed for Starting Vegetable Seeds
Here are supplies you’ll need for starting vegetable seeds indoors. You can click on the pictures or links for more information on each.
Seed Starter Tray
If you plan to start multiple vegetable seeds, it’s easiest to use a seed starter tray like this one that I use. Starter trays are affordable, convenient, and effective.
I always recommend starting multiple seeds at one (at least 6 per vegetable type) to be able to weed out any weaker-looking vegetables for final planting. Also, depending on the crop, you may need several plants to have a sizeable harvest. Starter trays make keeping track of different vegetable types easy.
Starter trays normally come with a lid that makes keeping your soil moist a breeze for germination. Also, after germination, the smaller soil depth makes watering significantly easier than using a large pot, where you have a larger risk of over- or underwatering your vegetables.
Some people use paper egg cartons or other containers for seed germination, but I like the convenience of starter trays, which come with a lid and bottom tray to catch excess water. Also, I can reuse them for every growing season.
If you want to directly plant your seeds into their final pot to avoid having to transplant them later, then you can use a large pot at this stage instead. Just ensure your pot is actually large enough to accommodate the vegetable’s full life cycle.
Research what soil depth and space your particular vegetable needs. As a general rule of thumb, a pot that is at least 10-inches in circumference and 12 inches deep would be a minimum, like this pot. Also, ensure your pot drains well.
I actually like these 3-gallon cloth bags for most of my vegetables, since they provide ample soil depth and spacing and discourage the roots from balling (i.e. overcrowding). Since they are rather large, you can even plant two or three smaller vegetables in the same pot.
You should ask a local nursery or gardener what vegetable varieties tend to be successful in your particular area, because varieties aren’t universal in the growing conditions they prefer. If you’re new to starting vegetable seeds, best to plant a bunch of seeds for trial and error. You can even try a variety pack to see what you can grow best.
Most seed packets come with dozens of seeds, so if you use a seed starter tray, you can plant many seeds at a time and weed them out.
You should use seedling soil to germinate seeds, since seedling soil has the the ideal composition for promoting seedling root growth.
As discussed under sunlight requirements, your emerging seedlings need a good source of light. Some seeds sprout in as little as two days, so you should have your light arrangement figured out fairly quickly.
We bought full-spectrum LED lights to hang over our seedlings. Although we bought T8, 6000 kelvin, 4-foot LED lights, T12 will also work.
We bought shop light mounts to hold the LED lights, and to be able to hang it over tables in our garage. We constructed our own grow station to save costs, but you can buy more assembled ones like this one.
Since we can adjust the shop light chains, we’re able to raise or lower the lights depending on the seedling heights. Another option is to have individual trays or boxes under your individual seed starter trays to raise them when needed compared to other seedling under the same lamp.
6 Easy Steps for Starting Vegetable Seeds: From Seed to Seedling
Getting seeds to germinate is actually quite simple, but the process can seem daunting to beginners. Fear not. As long as you provide the right conditions for your seeds, they will germinate and grow into happy seedlings.
The first time I planted vegetable seeds, I was pleasantly surprised by how quickly and easily the seeds sprouted!
Here are basic steps on starting vegetable seeds, so that you can also get past the initial hurdle in growing your first vegetables.
Step 1: Prepare Your Container
Step 2: Plant Seeds
Although seed packets mention specific soil depths, you needn’t be super precise. A hole about ¼ to ½ inches deep should suffice. Just drop the seed in and lightly brush soil back over it, without packing the soil down.
Note: if you are not using a seed starter tray (i.e. not using a container with separate seed compartments), then ensure you leave at least 1 ½ inches of spacing around each seed. The more space, the better, so that you needn’t worry about separating roots as carefully if you transplant the individual plants later.
Step 3: Water the Seeds
Water your seeds with a very light stream of water to avoid unearthing the seeds you just planted. The soil should be thoroughly saturated, so be sure water can drain from the bottom to prevent overwatering.
If you are using a seed starter tray that comes with a bottom tray, you can fill that tray with some water instead and wait for the soil to soak up the water from the drain holes upwards. Once you see the soil most at the top, then you will know all of the soil has been saturated.
Never overwater your seedlings, especially if your container has no drain holes. If the soil is too damp, the seeds and roots can rot.
Step 4: Cover Your Seed Tray
If you use a seed starter tray, it should come with a lid. Once the soil is fully saturated with water, put the lid over the seed tray. You want to prevent air from entering or escaping so that the container can retain its humidity until the seeds germinate.
If you aren’t using a seed starter tray, then place whatever airtight covering you can find over it. A clear lid is ideal to allow you to check for germination without having to lift the lid. If you have no lids available, just ensure the soil remains most at all times.
Keep your trays somewhere warm to encourage germination. We place ours on top of the refridgerator.
Step 5: Wait for Germination
The soil should remain adequately moist before the seeds germinate, but if the soil happens to try it, add more water. Once you see stalks poking out of the dirt, congratulations! You successfully germinated a seed!
Step 6: Provide Adequate Light and Water
Once any stalks emerge, remove the lid and place the tray under an LED light, or other full-spectrum lighting. We keep our light on a timer to run for about 12 hours during the daytime.
If using an LED light, the sprouts should always be 2-3 inches under the light. Any further won’t provide enough light. Thus, as the seedlings grow, you’ll have to adjust the height of your lamp and/or elevate shorter seedlings accordingly so that all seedlings remain 2-3 inches from the light.
Water your seedlings whenever the soil is dry. Your environment will influence how quickly the soil is depleted of water, so regularly check the soil until you can derive a pattern of when you normally have to water the seeds.
Since our seed starter trays provide adequate draining, I never worry about overwatering. I water when the soil looks dry and simply let any excess water drain out.
What’s Next for Your Seedlings?
How quickly you transplant (i.e. transfer) your seedlings depends on several factors. One, if your starting container large enough to allow more root growth, then you won’t have to transplant it right away (or at all, depending on the size of the container).
Generally speaking, I wait until the seedlings are at least 2½ inches tall with a few sets of leaves before transplanting. Under no circumstance should you transplant a seedling before it gets true leaves. The first two “leaves” that sprout from a stalk are cotyledons, which are parts of the seed embryo, but not true leaves.
More importantly, I consider how crowded the roots are. If the roots are balling around the soil (i.e. if the roots are holding the soil together in a fairly clean clump when lifted out of the pot), it’s definitely time to transplant. Whereas if the roots have barely invaded the soil, then the plant still has plenty of soil space to go.
Once you are ready to transplant, you can read our next article, Beginner’s Cheat-Sheet to Transplanting Seedlings – 5 Easy Steps. We will see you there!
If you have any comments or questions about this article on starting vegetable seeds, please leave them below.