There are some plants that will thrive much better sown direct rather than in seed trays. Seed sowing instructions usually list when this is the case. Some plants can be grown successfully from either starting point.
Broadcast sowing is used for growing lawns from seed and also when we want swathes of wildflowers, annuals or perennials.
Use our previous post on preparing beds and borders to ensure you have a good tilth; you need the soil to be well broken up into a texture that ranges from powdery to very small clods no more than 2cm in diameter. It can be beneficial to do this 2 or 3 weeks before sowing, allowing the first set of weeks to grow and then removing them to provide a more weed-free environment for the seedlings you want.
Mark a space you wish to sow in, horticultural sand, perlite, vermiculite or a weighted string or rope can be used to mark irregular spaces. Garden lines (string tied between stakes) can be used for straight lines.
Scatter the seed. For lawns follow the instructions on the seed box. For annuals and perennials there will be instructions on seed packets or as a general rule you are looking for a thin sowing of 5-10 seeds per seed packet sized piece of soil. A thinner sowing will promote the young plants growth.
Cover with soil preferably using a rake or hand tool, moving the soil at right angles. If using a hand tool be careful not to bury too deep. You are looking for around 2-4cm of covering (seed packets will give more specific measurements).
Water with a fine rose ensuring the area is moist. Try to keep the area moist particularly if we have hot sunny days or windy days (wind removes moisture as well as sun).
Once seeds germinate, continue to keep moist until their 2nd or 3rd set of true leaves. Thin out any that have germinated very close, potentially transferring the seedlings to sparser areas. Once you have 2 or 3 sets of true leaves, encourage deeper rooting by watering well a couple of times a week for 2 to 3 weeks so the plants follow the water into the soil and eventually are able to go some time between rain or watering.
Many vegetables are started using this method as it puts plants that don’t like root disturbance into their final growing position.
It’s also a very reliable method after the risk of frost has passed for all sorts of plants, as it is likely to provide better sunlight and better nutrition than sowing in trays.
It also provides us with a second chance to grow some varieties that haven’t worked out when grown in trays and pots. Beans, courgettes and lots of brassica can get leggy if light conditions are not great in trays.
Use steps 1 and 2 above to get the ground ready.
Using a draw hoe, garden cane, broom handle or spade, draw a drill against a garden line. Different seed will need different depth, check seed packets or the internet.
Water into the drill using a can without a rose but be careful not to damage the drill, you are looking to create moisture in the drill and the soil below to create good growing conditions.
Either thinly sow along the length of the drill (start with very thin and get to the end of the drill, then if you have enough seeds you can add a few more to the start of the drill. It is easy to spread too heavy and then run out of seed before the end of the drill and moving seeds along has risks such as pushing them too deep). Or place seeds in stations, often the seed packet instructions will be 2 or 3 seeds evenly spread at equal distances in the drill.
Use whatever tool you used to make the drill to move soil back over the seeds leaving an even and flat surface.
You can water over the drill line using a fine rose, but enough moisture will be available to the seeds if you watered the drill well.
Mark the drill with a plant label or stake to remember where it is. If you have a few garden lines, leaving them in the ground until germination can help you to know exactly where it is across the bed.
Keep the line moist, particularly if we have had hot sunny days.
Once germination has taken place, wait until you have some true leaves before thinning. Sometimes it can be easier to thin slowly over a few weeks as this allows you to see which seedlings are growing the strongest. Eventually you want the advised spacing in place.
Follow instruction 6 above to water wisely and establish thriving plants.