Sowing Seeds in August

It’s August which means it’s time to start sowing seeds. August is the best time to get out those seed packets and hone your sowing, spacing and thinning out skills.

Since March we have been putting the building blocks in place for a successful food garden. You’ve done the planning and preparation, and now it is time to start sowing.

In warm frost-free areas, you can sow seed directly into the soil. However, in many areas it is not advisable to sow in situ until after the last frost.

Instead of losing valuable growing time, you can sow the first batch of seed into pots or seedling trays. Keep them in a warm, sheltered place. By the time temperatures have risen and the soil has warmed up, the seedlings will be ready to plant out.

Sowing seeds in pots or trays

Our food garden expert, Di-Di Hoffman, starts his vegetables in 10 cm pots, rather than seedling trays. This is because the greater depth of soil they hold makes growing and transplanting easier. If you are sowing seeds in pots, you can sow three seeds per pot for small to medium seeds. For larger seeds, such as beans, sow one seed per pot.

Use a good quality potting soil or a mix of equal parts of sifted garden soil and fine compost. Palm peat also works very well for germinating seeds. The soil texture should be fine so that there is good contact between the seed and the sowing medium. If the soil is is too coarse then air pockets form around the seed. The air pockets can trap water and cause the seeds to rot. Keep the soil moist, but not wet, during the time the seeds take to germinate.

Di-Di finds that sowing seeds in pots can advance planting times by up to three weeks. In addition to this, if you are careful when transplanting, it can reduce transplant shock. Sowing in pots also also allows one to manipulate succession planting.

Sowing seeds in situ

Once the soil is warm enough, you can sow most vegetable seeds directly into the veggie garden. Most vegetables will germinate easily and sowing directly into the soil is the easiest way to get things going.

Spacing

Spacing refers the amount of space you leave between each plant. It is a critical factor in a small vegetable garden. Spacing is also determined by soil quality and the time of year.

In poor soil, space your seeds further apart so that the demand on nutrients is not too concentrated. Well-spaced plants are more drought resistant because there is more space for the roots to look for water.

Plants can be closer together at the beginning of the season. It is advised to space your seeds further apart in summer as this is when growth becomes more vigorous.

Spacing further apart also allows for better air circulation between vegetables. This helps to prevent fungus infections, especially in wet, humid weather.

All seed packets have recommended spacing guidelines. Follow these guidelines until you have gained enough experience to adjust them according to your own observations.

Depth

The depth that the seeds need to be sown at is also on the seed packet. Sowing at the correct depth is important. Be sure to follow this depth consistently otherwise the seeds in the batch will germinate sporadically. If you sow your seed deeper than necessary, it can take a week longer to germinate. Sowing seeds too shallow may cause the seed not germinate at all.

Ways to sow

Scatter sowing:

When scatter sowing, make sure the bed is totally level. If the bed it is not level and it rains, the seeds will all be washed to the lowest points.

Rows:

When sowing in rows distribute the seed evenly along the row; this is easier if you use a planting stick with markings at 5 cm intervals. Put the stick alongside the row and sow in little dribbles, then fill the row with sieved compost. This aids germination because it is easier for the germinated growth to push through, especially in clay type soil. It also provides nutrients to the seedlings.

Individual holes:

Use this method for larger seeds – Di-Di advises using a cone shaped dibbler or sharp pointed tool to make the hole. (Using a blunt tool compacts the soil.) After dropping in the seed, fill the hole with sieved compost.

Watering

When sowing seeds in August, water the bed two to three days before sowing so that the soil is just damp. Later in the season you can water the bed a day before sowing. Don’t sow in soil that is either dry or soggy. Don’t allow the soil to dry out during germination. Due to the rain in August and September, there is usually not much danger of this happening.

During very hot months, you can cover the beds with a shade cloth. This keeps them cool and also saves water. As a general rule, you should water your seed beds once a day. You don’t need to water too deeply because most seed is not much deeper than 5 cm.

If possible, fit the watering can with a very fine rose. Beware of big spurts of water as this can wash away your seeds. To avoid this start watering away from the seed bed then bring the spray over the bed. Finish by watering away from the bed again.

Fertilising seedlings

Once the seedlings have sprouted, it is a good idea to feed them. This will give them a good boost for vigorous and healthy growth. You can use a low concentration of liquid fertiliser, preferably an organic kelp-type fertiliser.

Thinning out

Start thinning out once the seedlings have grown a few centimetres tall. This step is critical because plants growing in a clump compete for water, nutrition, light and growing space. Snip off the plants at ground level; it is less disruptive than pulling them out.

You can continue thinning out until you have achieved the final spacing. Use the plants you remove in salads and stir-fries.

Seed viability

Vegetable seed is generally viable for two to three years if stored correctly. If you have leftover seed, fold the top of the seed packet and secure it with a clothes peg. Store it in a sealed container in a cool place.

On some seed packets, especially those containing hybrid seed, you may see a cautionary note. This usually notes that the contents are ‘treated seeds, not for human consumption’. This means the seeds have been treated with a fungicide to prolong the period during which they will be viable.

What to sow in August

In warm, frost-free areas, you can sow the following vegetable and herb seeds in situ. In other areas, sow in pots or wait until after the last frost.

Herbs: chillies, nasturtiums, Italian parsley (flat leaf parsley) and parsley (curly leaf)

Vegetables: beetroot, brinjals, cabbage, carrot, lettuce, peas, peppers, radishes, rocket, runner beans, spinach, Swiss chard and tomatoes.

Article by Alice Spenser-Higgs with information by MayFord Seeds and Di-Di Hoffman of Bouquet Garni Nursery.