Sow seeds for spring planting
Carter Gareth Carter is general manager of Springvale Garden Centre
THE BITE OF WINTER was present this past week with heavier frosts than we have had for years in Whanganui. Covering tropical and frost sensitive plants with microclima frost cloth on clear nights is advisable. Alternatively use Vapour Guard, also known as Liquid Frost Cloth. This can be sprayed onto plants to give frost protection. It should be reapplied after three to four frosts. In the midst of the frosty mornings there is flowering cheer from early daffodils, some magnolia varieties are now out in bloom, daphne are offering lovely fragrance and many grevillea and erica varieties too are looking spectacular. Spring is now six weeks away and it is time to start the sowing of seeds indoors of summer growing vegetable and flower plants. For those who are keen to save money on their gardens, then growing some of your vegetable plants from seed is a good place to start. Most seeds take 14 days to germinate, then another 14 days to get to the transplanting stage which if sown over the next week will take us to around mid-September. If these are then transplanted into individual pots and grown on for another three weeks, then they will be ready for planting out into the garden during late September. This is when the risk of late frost in Whanganui has generally past and both day and night temperatures are rising. Raising plants successfully from seed is a good way to get many plants cheaply. It is also very rewarding to go through the stages from choosing what you want to grow, to choosing what to grow them in, direct into the soil or into some type of container. Then pricking them out into larger pots and finally into your own garden. The whole adventure continues as you grow them to flowering or harvest. Some of the flower seeds that can be sown now include petunias, impatiens (busy lizzies), bedding begonias, lobelia to name just a few. Some of the vegetable seeds that can be sown now include tomato, capsicum, eggplant, zucchini, cucumber, lettuce, pumpkin, watermelon and cold sensitive herbs such as basil can also be started off in the same way. Here I will outline some tips for being successful at growing plants from seeds. Firstly, reading the packet is a good start, but if you’re taking the time to read this article then you will probably also read the seed packet. If you are sowing cold sensitive plants like those mentioned above, then they need to be sown indoors in pots or trays. The tray should be filled with a specialty seed raising mix such as Tui Seed Raising Mix or Yates Black Magic. These are blended to ensure the right water holding capacity, fertiliser requirement and will often contain a fungicide which helps prevent seedlings dying after they have germinated. A mistake sometimes made is to use garden soil in trays. Garden soil tends to retain too much moisture as it doesn’t escape out the bottom of the tray/pot. The water then fills up the air gaps in the soil which the roots need to breathe. The seedlings then can effectively suffocate and die. In a garden situation the soil is generally much deeper and thus water can drain away from where the roots would be growing. Seeds should be sprinkled evenly on top of the seed raising mix and then covered lightly with more seed raising mix. The depth of this will be specified on the back of the packet. A general rule is to cover the seed with an amount of seed raising mix that is twice the diameter of the seed. Next, lightly firm the mix to ensure direct contact of the seed with the mix which holds moisture and nutrients. Then water gently to thoroughly moisten the soil without washing the seeds away. Cover the tray with newspaper and place in a warm location. Check daily that the mix has not dried out and to see if any seedlings have germinated. As soon as you see seedlings coming through remove the newspaper and ensure they are in a light position. It is at this stage that many people go wrong; seedlings left in a position near a window but not rotated regularly can become “drawn”. This means the seedlings have elongated or stretched as they crave more light that they are receiving. The result of this is a weak plant that will not transplant well into the garden at a later stage. As soon as seedlings have a second set of leaves, they should be carefully transplanted (pricked out) into individual pots. Plastic pots or yoghurt pottles with holes drilled in them can be used. Peat pots are great to use as they are fully biodegradable so when it comes to planting into the garden they go in pot and all, meaning zero root disturbance and no setback in plant growth will occur. Egg cartons and cut down toilet rolls can also be used to the same effect. Once potted individually, seedlings should be grown on until they are approximately 15-20cm high and all danger of frost has passed. Once we are into mid-September seedlings should be gradually hardened off, bringing them outside for a few hours a day will allow them to acclimatise. Many seeds such as beans, carrots, radishes and corn should be sown straight into the garden. You need to ensure the weather will be warm enough for these crops since they will be exposed to the elements from the moment they are planted. Carrots and radishes can be planted now but corn and beans are best sown in the garden from October to December. When sowing seeds in the garden, soil preparation needs to be the first consideration. Soil needs to be dug over and all clods broken down finely. Next water the soil and then make a shallow groove along which the seeds should be sprinkled, lightly covered with soil and then water again. Marking each end of a row with stakes will help ensure you remember where you have planted your seeds. Watch out for cats and birds. Cats sometimes presume that the finely worked soil was to be a litter box and birds presume it an easy place to shop for worms. Sometimes bird netting can be a deterrent.