How to Grow Vegetables from Seed

Growing vegetables from seed is a rewarding activity, and ultimately becomes an integral part of your self-sufficiency journey. Far more cost effective than buying seedlings, growing from seed also allows you to learn a whole host of new skills. Seeds are typically much cheaper than buying established plants or seedlings, and with a small initial investment, you can grow many plants from a single pack of seeds plus keep the resulting seeds for the next season.

Plants that are grown from seed tend to have stronger root systems compared to seedlings that have been handled or transplanted, and can be more resilient in the long term. This is because plants will naturally adapt to your individual garden microclimate over time, so growing from seed then collecting seed from those plants and using it in subsequent seasons strengthens plants with each successive generation. Not to mention, you can try all sorts of varieties, and spend more time in the garden; what’s not to love?!

Get Your Seed

One of the first things you’ll need to do when planning to grow vegetables from seed, is buy the seed.

There is a huge number of seed companies to buy from no matter where you live (here is our round-up of Australian sellers). In-person sources might include local nurseries, hardware shops, supermarkets and local gardening groups. Commercial seed packets usually have a sow-by date on the back, because all seed reduces in viability as it ages. If in doubt, buy some fresh seed.

If you have some older seed on hand but are not sure if it is still good, it’s easy to test its viability. To do this, wet a piece of paper towel, spread 10 seeds on it, and wait to see how many germinate. This is also a handy trick to use if you’re a beginner or you’ve bought new seed from an unknown-to-you supplier. This way, if the seed doesn’t germinate in soil, you’ll at least know that the seed itself is not at fault.

Time it Right

All vegetables have an ideal climate or season in which they grow, and will usually either fail or fail to thrive outside of these conditions. When planning to sow seed, read the packet instructions carefully to ensure that you are intending to grow your food plants at the right time (i.e. within that plants preferred temperature range). Remember that the info on seed packets is often highly generalised and skewed towards temperate climate zones, so don’t hesitate to do further research if you feel unsure.

If you live in a very hot or a very cold climate zone, timing both sowing and planting out can be crucial. Pay close attention to both the length of your growing season and time to achieve mature fruit, and note that with some crops, your season might be shorter than particular vegetables require. In this case, you will probably need to either start seeds indoors under heat and lights or under netting in the shade.

As an example, I only have a very short & mild winter here in subtropical seQLD, so I sow brassica seeds on Valentines day in order to grow fruit before the weather warms up again in September. (For more detailed south-east QLD climate info, see our planting guide here). Conversely, those in cold climates might experience random late frosts and need to keep seedlings indoors for a significant length of time.

What Soil Should I Use?

Lots of soil mixes will successfully turn your seeds into seedlings: there is no *one* correct answer to the soil question. If you’re a beginner, a bagged commercial seed raising mix can be a good place to start. While such mixes aren’t the cheapest, they are a safe place to start, as they are fine, sterile, easy to work with and contain the right amount and balance of nutrients.

More experienced gardeners might use a home-made mix. This might include things like sieved compost and/or quality potting mix, coir, small amounts of aged manure, sand, garden soil and worm castings.

As your gardening experience, knowledge and confidence grows, you’ll find yourself experimenting and changing seed raising mixes until you land on one you’re happy with.

Sowing

First, decide what type of pots or containers you will use for raising seedlings.

Single-cell blocks are very popular, as they separate each seedling and are easily kept hydrated via a water-filled tray underneath. You can also sow several seedlings into any size plant pot, or of course, sow seed directly into its final position. Personally, I use planter boxes when raising seedlings for transplant, as I find them the easiest to manage. There’s enough room in a planter box to space seeds out, and it makes quick work of planting out, as I can remove several seedlings at once and separate them easily.

To sow seed, place your chosen seed raising mix into your pot and water it well. Make sure there are no lumps or clumps in the mix, as these can impede germination and growth. Sow your seed as directed. Note that most seed barely needs to be covered under soil, and some (often flowers) will need light to germinate. As a general rule, tiny seeds need only a dusting of soil on top of them. Medium-sized seeds can be buried as deep as they are long, and larger seeds (i.e. beans and pumpkins) can be buried a couple of centimetres (an inch) deep.

Remember that tiny new seedlings need to be able to move through the soil above them and grow beyond it, so don’t put too much on top of them. Once your seed has been sown into damp soil, you shouldn’t need to water it for another day or two.

Raising the Seedlings

The trick to triggering seed germination is to keep seeds *moist*. If the soil is too wet they can rot or drown. If the soil is too dry they’ll die from lack of water just as any plant will.

To this end, seed and tiny seedlings are best *misted* rather than watered– water pressure from a standard hose is fine for established plants, but is usually too strong for the germination stage.

Most modern hose nozzles will have some sort of ‘mist’ setting. You want to be watering as gently as possible, because seedling stems are so fragile that they easily flop and drown.

Frequency of watering depends on your climate, as does position. My humid subtropical climate dictates that my seeds are sown in late summer, placed in the shade and misted 3 times a day. At the opposite end of the spectrum, those in cold climates will be sowing at the end of winter, perhaps indoors under heat and lights, misting every 2 days, and/or placing their seedling trays in the sun.

Essentially, you’ll need to position and water your seedlings so that they have mild growing conditions which will give them the best possible start.

Planting Out

Once your seedlings have grown their first set of true leaves, they are ready to be planted out or transplanted into larger pots. Planting out at the right time is crucial to the creation of strong plants. If you leave them until they have grown a second set of true leaves, this will be the longest you can leave them in the seed raising mix. This is because seed raising mix only contains enough nutrients to raise a seedling up to this stage- the seed itself also contains some energy, but only enough to allow germination. If you leave the seedlings any longer, the leaves will yellow, growth will stop and they will die.

When handling your seedlings for planting out, lift them by the leaves rather than by the stems. Surprisingly, the leaves are stronger than the stems at this stage. The stems of young seedlings have only a single channel through which water and nutrients can travel. Holding a seedling (even gently) by the stem often damages or squashes the channel, which is one reason that seedlings may not survive transplantation.

Make sure to leave some soil around the roots, keeping as much of the tiny root system intact as you can (if you find this part difficult, consider using seed raising pellets). Root disturbance can negatively impact a plants viability, so it’s important to keep this to a minimum. After watering the soil, plant out your seedlings in the late afternoon. Next, mist them gently. This should result in a thorough watering, but they should not receive so much water that they become ‘drowned’. Afternoons are always the best time for transplanting. Plants have a few cool, dark hours to start recovering from any transplant shock, while avoiding any extra stress caused by direct sun.

After planting your seedlings out to their final position and watering them, don’t water them for a day or 2. This gives the roots space and time to grow into their new environment- literally. Too much water too soon leaves no air pockets between soil particles, which is what roots need for growth. Think of these first couple of days as ‘time to settle in’.

Don’t be shy to cover new transplants for the first few days. They may need a little extra warmth or protection from the sun while they adjust to their new environment. Root disturbance in particular can cause transplant shock, which, as the name suggests, causes significant stress to a fragile young plant. Transplant shock is a subject all in itself, but in a nutshell it looks like a sad, floppy plant that doesn’t immediately respond to watering. Seedlings should recover within a few days, but even experienced gardeners will lose a few- so don’t lose heart- not every seedling is meant to make it to adulthood.