Whether you’re a seasoned gardener or a total beginner, there’s nothing quite like growing your own plants from seed, and there are a lot of tips and tricks that can take you from seed-starting misery to harvest satisfaction. Seed starting lets you choose from a wider variety of plants, enjoy an earlier (often longer) harvest, and experience the satisfaction (and occasional drama) of nurturing plants right from the beginning. This guide will walk you through the seed-starting process and help you get the best results from your efforts.
Ready to discover the secrets to successful seed starting? Let’s dive in!
Why start seeds indoors?
Gardeners decide to start seeds indoors for a variety of reasons. First of all, it gives you a jump-start on the growing season, which is especially helpful if you live in a region with a short growing season. Seed starting also allows you to grow unique or heirloom varieties that may not be available as transplants at local nurseries.
By starting your seeds indoors, you can control the environment — ensuring proper light, temperature, and moisture — giving your plants the best possible start. Plus, it’s a great way to save money since seed packets are typically much cheaper than buying fully-grown transplants, especially if you want a lot of them!
What tools and materials do I need for successful seed starting?
Before you begin, you’ll want to gather the right tools and materials. Here’s what you’ll need:
- Seeds: Choose seeds that are appropriate for your climate and growing conditions. Check the seed packet for information on when to start them indoors and transplanting times.
- Containers: You can use a variety of containers to start your seeds. Seed trays are popular, but you can use egg cartons, yogurt cups, or other small containers with drainage holes.
- Seed-starting mix: Regular garden soil is too heavy for seed-starting. Many soil options can do the job, but a light, sterile seed-starting mix will provide good drainage and air circulation while preventing diseases that can affect young plants.
- Labels: It’s easy to forget which seeds are which, especially if you’re starting many varieties. Use labels to mark each type of seed in your trays.
- Light source: Most seeds require plenty of light to germinate and grow into healthy seedlings. A sunny windowsill will sometimes work just fine, but many gardeners find that fluorescent grow lights or LED lights provide more consistent results. If your seedlings tend to look leggy, you probably need a stronger light source.
- Watering tools: Gentle watering is the key to avoid disturbing the seeds. A spray bottle or a small watering can with a fine spout works well.
- Heating mat (optional): Some seeds, like tomatoes and peppers, germinate best with warmth. A heating mat can help maintain a consistent soil temperature of around 70-75°F (21-24°C).
Gardening tips for beginners: Step-by-step guide to seed starting
Step 1: Timing!
One of the most important gardening tips for beginners is that each plant species has its own preferred planting time. Check your seed packets to find out when you need to start them indoors. Generally, you should start seeds 4-10 weeks before your region’s last expected frost date. For example, tomatoes and peppers are often started about 6-8 weeks before transplanting outdoors. Of course, there are plenty of plants you can start through much of the year, so always look at the information on your seed packet.
Step 2: Grab your seed-starting mix
Fill your containers with your seedling mix, leaving about a half-inch of space from the top to prevent spillage. Moisten the seed-starting mix with water before adding your seeds. The mix should be damp but not soggy.
I’ll be honest: seed starting mix is consistently the right choice for seedlings, but I often fill the bottom 2/3 of my pots with potting soil and the top 1/3 with seed starting mix. Potting mix is often cheaper than seed starting mix, and I find that once the seeds have started, the roots are happy to find the nutrition that the potting mix offers.
Step 3: Plant your seeds
It’s tempting to be creative, but one of the more important gardening tips for beginners is to follow the instructions on your seed packet for planting depth. The general rule is to plant seeds at a depth that’s twice their width. You often just press tiny seeds lightly into the surface of the soil without covering them. Once planted, gently firm the soil over your seeds. If you aren’t sure your seeds will germinate well, you can add more seeds than you want plant starts, but as you get more comfortable, you’ll want to make sure to give your little seedlings some room to grow (unless you’re planting microgreens! You can pack those in pretty tightly if you want because they aren’t going to need to develop.) When you find out
Step 4: Provide light and warmth
Place your seed trays in a warm location with bright light. If you’re using grow lights, position them a few inches above the seedlings and adjust the height of your grow lights as your plants grow. Seeds typically need 12-16 hours of light per day to thrive.
You might want to consider using a heating mat under the trays for seeds that require warmth, like tomato and pepper seeds. If your soil temperature is around 70-75°F (21-24°C), it can encourage faster germination.
Step 5: Keep the soil moist
It’s crucial to maintain even moisture while the seeds are germinating. Use a spray bottle to gently mist the surface of the soil or water from below by placing your seed tray in a shallow water dish for about 30 minutes to an hour. Avoid overwatering, which can cause fungal diseases like damping off.
Step 6: Thin your seedlings
Once your seeds germinate and the seedlings have grown a couple of true leaves (the leaves that appear after the initial seed leaves), it’s time to thin them out. (Thinning them out means removing the weaker seedlings so that the strongest ones have room to grow.) You can use small scissors to snip the weaker seedlings at the soil level to avoid disturbing the roots of the remaining plants.
Step 7: Feed me, Seymour!
Most seed-starting mixes are sterile and don’t contain nutrients. Once your seedlings have developed their first set of true leaves, you can begin feeding them with a diluted liquid fertilizer every two weeks. (I like to use liquid seaweed at this point.) To avoid over-fertilizing young plants, use a half-strength solution (or even less at first is fine).
Step 8: Harden off your seedlings
Before you transplant your seedlings outdoors, it’s essential to acclimate them to the outside environment. This process is called hardening off, and even though it might feel like your seedlings are ready and they’ll be fine, this is one of the more important gardening tips that beginners should know. About a week before transplanting them, start putting your seedlings outside for a few hours each day, gradually increasing the time they spend outdoors. During this transition, protect them from direct sunlight, wind, and harsh weather.
Step 9: Transplant
Once your seedlings are hardened off and the weather has warmed, you can transplant them into your garden or larger containers. Be gentle when handling the seedlings, and try to keep the root ball intact. However, if your seedlings have been in their pots for longer than you expected and their roots are winding around the inside of their pots, you do want to gently tease the roots apart before you put them in the soil. Gently but firmly press the soil in around your seedlings to make sure that all of the roots are in contact with the soil, and water them well after transplanting to help them adjust to their new environment.
Gardening tips for beginners: Common seed-starting mistakes to avoid
- Overwatering and underwatering: Too much water can lead to fungal problems, while too little can dry out the seeds. Keep the soil consistently moist, not soggy.
- Insufficient light: Weak, leggy seedlings are often the result of insufficient light. Ensure your seedlings get adequate light from a bright window or grow lights.
- Skipping the hardening-off process: Transplant shock can be fatal to young seedlings. Always harden off your plants before moving them outdoors.
- Crowded seedlings: Thinning seedlings is essential for strong growth. Crowded plants will compete for light, water, and nutrients, resulting in weaker growth.
Seed starting: One step closer to self-sufficiency
Once you get comfortable starting your own seeds, you’ll be amazed that you ever tried anything else. With the prices of plant starts today, having far cheaper, stronger, and healthier seedlings for your garden whenever you need them is unbeatable. Plus, you get to start the varieties that make sense for your microclimate and soil.
Starting seeds indoors is a rewarding process that gives you complete control over your garden from the earliest stages. With a little attention to detail and care, you can grow robust seedlings that will thrive once you transplant them outdoors. It’s a process that allows you to experiment with different varieties, grow unique plants, and get a head start on the gardening season. Happy gardening!
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