How to Grow Strong, Healthy Seedlings

The key to a healthy garden starts with strong seedlings. Whether you start your garden from seed or buy seedlings from a provider, the overall success of your garden depends on the quality and health of the seedlings you start with. Weak seedlings usually become slow-growing, unproductive plants that invite pests and other problems.

Starting from seed is slower and a little more challenging, which is why not everyone does it. These first steps, used by professional growers, will help you master it.

1. Decide the best time to plant your seeds

As with most gardening, seedling success has a lot to do with timing. Start too early and an unexpected frost might kill your plants. Start too late and they may not have enough time to mature. Seeds often come with a planting schedule on the packet, and if yours do not, there are planting calendars you can reference.

2. Gather the supplies you will need

Healthy seedlings need only a few things. First and foremost, the seeds. You can order high-quality seeds online or from seed catalogs, and local garden shops and seed swaps are great sources too. Buying online often lets you read reviews from other gardeners, which gives you an idea of what to expect.

Wherever you get them, use relatively fresh seeds. After a year or two most seeds do not germinate as well, especially if they have not been stored somewhere cool and dark.

Besides seeds, it helps to have:

• A seedling tray (a food storage container or glass baking dish will also do)
• Rockwool cubes and vermiculite
• Grow lights (fluorescent shop lights are an inexpensive but effective option)
• A small fan
• An outlet timer

3. Plant your seeds

Many gardeners find that soaking seeds overnight in a shallow bowl of water improves and speeds germination, and this works for most plants. Do not bother soaking smaller seeds, such as lettuce and greens. They are too easy to lose, and they usually sprout well anyway.

Before planting, soak your rockwool cubes thoroughly for about half an hour. Then plant the right number of seeds for the crop:

• Lettuces and greens: 6 to 12 seeds per cube
• Herbs: up to 6 seeds per cube
• Vegetables with larger seeds, such as tomatoes, cucumbers, peppers and beans: 1 to 2 seeds per cube
• Anything else: follow the instructions on the seed packet

Once the seeds are in, fill each cube's seed hole with dry, coarse-grade vermiculite (only half full for smaller seeds). This keeps enough moisture around the seeds for them to germinate.

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