After a pretty serious cold snap last week, we are now back into spring temperatures.
The signs of spring are continuing. I keep mentioning the magnolias which seem to be flowering for longer this year. My favourite flowering cherry tree, Prunus Awanui, is now starting to blossom too. These flowering cherry trees have a few blooms on each popping open in the garden centre and the ones in Ridgway St too are starting to flower – these are worth a look in the coming couple of weeks. Tulips are coming into bloom too; it can be beneficial to give them a side dressing of bulb fertiliser as the flowering subsides. This will help build reserves in the bulb which will be determinant of next year's flowering display.
For those of you wishing to grow your own vegetables this year, now is an ideal time to begin. As well as the enjoyment and satisfaction of harvesting your own produce, there are also economic benefits to growing your own vegetables. Not to mention the proven fact that all vegetables are more nutritious when they are eaten fresh.
When preparing for a vegetable garden, the first step to ensuring success is preparing the soil. The removal of weeds is imperative. If the area is infested with oxalis, paspalum, couch or another invasive rhizomatous spreading type weed, then you will need to use a systemic weedkiller to ensure through removal of weeds, otherwise you will likely have a losing battle with your vegetable garden. Many weeds will be able to be successfully cleared by hand, and even dug into the soil, adding to create more organic matter. If you are unsure whether the weeds you have are invasive you can bring in samples to the garden centre and check with the staff.
Depending on the soil type, the addition of mushroom compost or poultry compost is highly recommended. A balanced fertiliser such as Ican Organic Vegetable Food is also a great product for use prior to planting and as a side dressing later.
These products will help with both soil structure and fertility which need to be addressed regularly for a successful vegetable garden. Vegetables take a lot of nutrients from the soil so ongoing regular additions of compost, pelletised sheep manure and Ican Organic Vegetable Food will replace these as well as producing a more friable soil suitable for vegetable growing.
Most vegetables prefer a neutral pH to alkaline soil i.e. pH 7-8. It is recommended to dust the soil annually with garden lime to maintain the slightly alkaline soil and improve the soil structure. An alkaline soil increases the availability of many nutrients in the soil and makes them more readily available for plant uptake.
Vegetables to be planting now
Cabbage can be planted now in full sun in a well-drained fertile soil. Purple leaves are a sign of being short of nitrogen – feed with a sprinkle of Tui Vegetable Food or Yates Dynamic Lifter for leafy vegetables.
Kale has become recognised as a "superfood". Its requirements are like other brassicas (cauliflower, broccoli etc). It matures in 60-70 days and can be used cooked or fresh, finely chopped into salad or coleslaw.
Broccoli is an easy vegetable to grow. Plant in full sun in a well-drained fertile soil. Be wary of slugs, snails and caterpillars. Broccoli matures to its best in 40-70 days, quicker than cabbage and cauliflower. Plant 30-45cm apart. Most broccoli will continue to produce an abundance of shoots after the main head has been harvested so don't be hasty in pulling the plants out.
Cauliflower should be planted in full sun in a well-drained fertile soil, like cabbage and broccoli. Slugs, snails and caterpillars can be a problem but are easily treated with slug pellets and derris dust. As your cauliflowers start to develop, snap some outside leaves over the heart to prevent burning and discolouration from the sun.
Celery's flavour is hard to beat when it's home grown. Plant 20cm apart, water and feed regularly. It matures in 100 days.
Lettuce varieties include the hearting and frilly varieties which you can harvest a leaf at time, allowing the remaining plant to keep growing. Lettuce can be grown in pots and troughs if you are limited for space, and of course in the garden. Plant in fertile, well-drained composted soil or potting mix. Space 30cm apart and water and feed regularly. It is also good in a glasshouse.
Spinach has become very popular. It grows easily, like silverbeet, and will be ready to start harvesting in 6-8 weeks.
Silverbeet is a very tough vegetable that requires little attention. Also in stores is a coloured selection which has stems shaded red and yellow tones. A colourful addition to the vegetable garden and often grown in the flower garden, these varieties taste the same as the traditional silverbeet.
Carrots are best grown from seeds and sown directly into the garden. They like to grow in nitrogen-poor soil, so a good tip is to plant after a crop of lettuces or other variety that will have depleted the soil's nitrogen levels. This is the same as with growing parsnips. Avoid using fertilisers with high nitrogen levels which will cause the carrots to "fork".
There is more that can be planted now and is available in stores in punnets including onions, spring onions, garlic, parsley, coriander, celeriac, rocket, spinach, mizuna, chinese cabbage (tatsoi), broccoflower, chicory and more.
Tomatoes and other heat-loving vegetables, such as capsicums, chilli, courgettes, cucumber and pumpkins, are all becoming available at garden centres now. Many people are planting these out now into glasshouses, cloches, pots and in sheltered parts of the garden where protection can be given from any late frosts and cool overnight temperatures. For those with more exposed garden situations, it's best to wait to plant your first tomatoes a week or three, depending on weather conditions and soil temperatures. Generally in Whanganui the last week of September is regarded as a safe time to start planting tomatoes outside. The same timing applies to growing beans and corn which are best sown directly into the garden bed where they are to grow.
Vegetables in pots
A great way to get vegetables growing before the weather is warm enough for outside planting is to start them off in pots. Try growing an early tomato in a pot. It can be a great way to get ahead of the game and allows you the option to move it inside if the weather turns nasty. I planted some in 35 litre pots last week and they are taking off nicely, sitting on my sheltered patio.
Growing vegetables in pots is great also if you are limited for space. Container vegetable growing is increasing in popularity with specialist potting mixes such as Tui Vegetable Mix for general vegetable plants, as well as specific blends such as Tui Strawberry Mix and Tui Tomato Mix. The key to growing in pots is watering and feeding. When the plants are getting large and the roots have filled the pot, a warm day will dry these out quickly. At this point, the addition of a saucer to the bottom of the pot can be of help or simply half-submerging the pot into a garden bed so it can suck water from the surrounding soil up through the drainage holes is another idea.
As the plant is limited to the nutrients in the potful of mix, these can be quickly exhausted. Fertilising little and often, reducing the opportunity for the leaching through of nutrient, gives the best results.
So give it a go - growing your own vegetables is rewarding and fun.
* Gareth Carter is general manager of Springvale Garden Centre.