The curcubit family, encompassing cucumber, zucchini, scallopini, pumpkin, kumo kumo, melon etc, are the most cold-sensitive of the summer vegetables.
These tender plants dislike lower temperatures and tend to collapse when it drops much below 10C. However, with warmer temperatures (15C-plus) they romp away, growing at a rapid rate with cucumbers and zucchini producing their first harvest within six weeks.
Many people enjoy watermelon and rockmelon. They are great summer favourites and can be easily grown in the home garden.
The watermelon has a thick, dark green skin and bright red flesh and is ready to harvest when the fruit sounds hollow when tapped. The rockmelon fruit has a rough, thick skin and bright orange flesh and is ready to harvest when the fruit pulls easily from the stem.
Both fruits can be eaten chilled for desserts, used in salads and as a garnish. One of my children has a great interest in growing plants and growing a watermelon in a pot the last few years has been a rewarding experience.
Eggplant, capsicum, chilli and tomato plants all need heat to thrive. Although they will survive in temperatures above 5C, they tend to sulk and, like the curcubit family, prefer to be in 15C or more. Now is a great time to plant.
If you want to get a jump start on your crops, many of these plants are available in stores now in larger sizes. This week I spotted eggplant, tomato, capsicum and chilli plants covered in flowers with fruit already set on them.
Beans come in two varieties
Two warm summer crops that are best planted as seeds directly into the garden bed they will grow in are beans and corn. Beans come in dwarf and climbing varieties.
Dwarf beans form a self-supporting bushy plant growing about 25cm tall and wide. They are quick to reach harvest and are ready for eating about seven to eight weeks from sowing. Planted now, they will be ready for Christmas dinner.
A highly recommended top-producing bean variety is “Supreme” in the Ican Chefs Best Seed Range. It is high-yielding, with strong disease resistance, and has straight 14cm-long beans set high on the plant for easy picking. The pods are distinctively glossy, very fleshy and have excellent flavour.
Supreme is ready over a two to three-week period so making a number of sowings every three weeks will give a consecutive harvest through the summer months. As a small-growing plant, they are an ideal vegetable to grow in containers if you are limited for space, as well as in the garden.
Climbing beans form a larger plant and need some support. A structure of 1.8-2m high is recommended, with trellis, wires or string being ideal for the tendrils to climb around. Climbing beans take about 10-12 weeks from sowing to start cropping but will keep flowering and producing beans for as long as the temperatures remain warm.
Some climbing bean varieties will form a tuberous root system that, if left in the soil, will regrow in future years. To leave your root systems to grow again the next year, the vines should be cut off above ground level as the plants die off in the autumn, rather than being pulled out roots and all.
A popular and top-performing climbing bean variety is Yates Scarlet Runner which produces very long pods for a good period through the summer months. It is known for continuous picking and heavy cropping.
Picking the beans young will give you more tender produce that has not had time to get stringy. An added bonus is the attractive flowers before they set pod. Scarlet Runner is also a perennial and will come up again each year.
Corn best sown before Christmas
My grandmother, a great gardener, has always said you need to make sure that your corn seed is sown before Christmas if you want to get a crop.
Corn is an easy-to-grow and productive crop that grows well in Whanganui. Seeds should be sown now directly into the soil and, to spread the harvest time, a second crop can be planted in mid-December; these will be ready for harvest between mid-February and March.
Corn is a heavy-feeding plant. Before planting, I recommend mixing Ican Organic Vegetable Food into the soil and then side-dress again regularly as the plants are growing. Corn is best planted in blocks, rather than rows, as this significantly improves the rate of pollination.
A highly recommended corn variety to grow is Tender Sweet which is part of the Ican Chefs Best Seed Range.
Its reviews live up well to its description: “Extra tender and full flavour. Very tender husks that do not get stuck in your teeth. Strong germination and vigour, high disease tolerance and early maturing. The best corn variety available.”
Time to treat for tomato/potato psyllid
It is important to now start spraying your potato and tomato plants with bee-friendly Yates Mavrik or Yates Success Ultra to protect against potato psyllid.
Prevention is really the key with this critter, as the generally unseen psyllid lands on plants and injects a bacterial pathogen into the plant.
This can go undetected for a while but will later show up, with plants showing stunting and yellowing of the growing tip. The edges of the curled leaves often have a pink blush. The stem may have swollen nodes and show browning of the vascular tissue.
After a while, infected plants develop a scorched appearance and plants can collapse prematurely.
Potatoes that are infected at an early stage develop numerous small tubers and, on tomatoes, the flowers often fall off the trusses and fruit that does develop can be small and misshapen. With the use of these sprays, it can be effectively controlled.
For more gardening information visit www.springvalegardencentre.co.nz.
