May New Zealand Gardening
May New Zealand Gardening.
With New Zealand Gardening you can feel a chill in the air and notice the day length shortening for New Zealand Gardening. The deciduous trees are colouring up before they drop their leaves. The boldest leaf colours appear when the days grow short and nights are cool, but temperatures remain above freezing. Causing the production of chlorophyll to slow and then stop. Then the chlorophyll disappears completely. This is when splendid autumn colours are revealed. The green chlorophyll normally masks the yellow, orange, red and purple pigments. These colours are present in the leaf throughout the growing season, but don’t show fully until the green chlorophyll is gone.
You might still be harvesting your last fruit such as apples or persimmon, if the birds haven’t got them by now!
It’s a good idea to rake up any dropped fruit and dispose of them off site, because pests such as codling moth can over winter from fruit, ready to re-infest you crop the following season.
Tasks For May New Zealand Gardening
General
Harvesting –
Regularly, preferably daily go around your garden with a bucket in hand and so you can get your produce while it’s at it’s best.
Propagation –
Many clump forming herbaceous perennials can be propagated by dividing the root system. Other herbaceous perennials, trees and shrubs can be propagated by taking semi-mature tip cuttings.
You select young healthy shoots from the lower outer extremities of the plant. Cut a piece below a node, generally between 100mm and 200mm long. Strip off the leaves from the lower 2/3rds and make a scrape wound with a clean blade about 10mm from the cutting base on two sides. If you don’t mind spending a few dollars then buy a rooting hormone to dip the cuttings into. It will increase the percentage of successfully rooted cuttings. You need to take more cuttings than you eventually want because there is usually a failure rate depending on how ideal the growing conditions are. Insert the cuttings into a container filled with clean coarse sand such as pumice sand or vermiculite if you don’t mind parting with a few more dollars. Water the growing medium and place a plastic bag over the container so it seals in the moisture. Then place it in a bright warm location without direct unfiltered sunlight. Be patient and ensure they remain moist until you can see roots growing out of the bottom of the container. Don’t pull them out to see if they’ve got roots because the roots will probably break off. Some easy to root plants will grow roots when placed directly into water if you change the water regularly to prevent it becoming putrid. When you have strong roots pot them into a larger pot and grow on.
Mulching
Apply mulches of compost now so it can break down into the soil over the following months.
Weeding –
You’ll often get a new crop of weeds germinating with the regular rain. I often let them grow large enough to identify whether they are desirable or not, then exterminate any unwanted weeds before they get away.
Food Gardening
Vegetables –
If you can get into a routine of walking around your produce garden each day, so you get the best fresh food you can.
In warm northern and central districts continue picking your beans, celery, Chinese cabbage, cape gooseberries, cucumbers, eggplant, marrows, peppers and tomatoes.
In colder central and southern areas the harvest of broccoli, cabbage, cauliflower, celery, Chinese cabbage, spinach, swedes, and turnips continues.
If your tomato plants die and still have a number of unripe fruit on it you can hang it in a sunny dry location where the remaining fruit will often colour up to ripeness.
Finish harvesting your pumpkins and store them in a dry dark location.
Collecting seeds –
Many vegetables and herbs will have seed heads on them now that can be harvested and stored for future sowing, or some can be immediately sown to save time, such as dill, parsley and rocket. Some hybrid plant seeds will not come true from seed. I.e. They’ll be different from the parent plant. To save the seed for storage you need to dry the seed head and then separate the seed from the dead plant matter and store it in a labelled paper bag or a glass container in a cool dry location until sowing.
If you’ve got empty beds you can apply compost. It’s a good idea to test the Ph of your soil which can be done with a test kit purchased from good hardware or garden centres. Ideally you want a Ph around 6.5. With heavy loam and clay soils you can add gypsum and garden lime and dig it into the soil before the winter rain makes it too wet for digging then it’s ready for early spring planting. When you dig your garden beds chop off any tree roots the are invading because they can out compete your veggies for water and nutrients.
Plant or sow a succession of vegetables at a rate that suits your consumption so you don’t get too much ready all at once.
May New Zealand Gardening
When planting seedlings or sowing seeds picture the size of a normal mature plant and allow that much space between each plant.
Veggies to plant or sow
Garlic can be planted out in all districts by separating individual cloves, and planting them about 5cm ( 2 inches ) below the soil surface and about 10 to 12 cm apart.
Northern and central temperate climate areas
May is the best time to sow broad beans. You can also sow broccoli, cress, lettuce, mustard, spring onions, peas, potatoes, radish,onions spinach and radish. broccoli, cabbage, Chinese cabbage, cress, kohlrabi, leeks, lettuce, mustard, onions, peas, potato tubers, radish, shallot bulbs, spinach, turnip.
Transplant seedlings of cabbage, cauliflower, and silver beet.
Southern and central cold climate areas
Sow – cress, lettuce, mustard, onions, shallot bulbs, and spinach.
Herbs –
Sow – parsley, dill, rocket, upland cress.
Continue harvesting for fresh use. If your herbs are going to seed consider either storing the seed for future sowing or sowing the mature seed directly back into the garden. The latter is easiest with parsley, dill and rocket.
Herb leaves can be dried on trays in a sheltered sunny location with occasional turning until dry. Then store them in an air tight container for future use.
Fruit Trees for May New Zealand Gardening
Pip and Stone Fruit –
Pick any remaining fruit.
Remove any fruit that have dropped on the ground and dispose off site, as these can be where insects and diseases can over winter and become a source of future infestation or infection with diseases.
If you’ve started a spray program earlier in the season you can give a clean up spray when there’s some calm dry weather.
Citrus –
You should be able to see your crop forming. Give the trees an application of fertiliser such as animal manure.
Berry fruits – The harvest is over so prune out the old wood and tie the new growth to a support.
Kiwifruit – Are becoming ripe and can be picked over a period as needed, since they can be left until needed for a wee while yet. They’re usually hard when you pick them, but you can speed up the ripening by putting them in a plastic bag with bananas or apples that give off ethylene a naturally occurring gas that speeds up ripening.
Raspberries, blackberries, boysenberries, and loganberries – The harvest is over, so prune out old wood and tie new growth to a support.
Strawberries – May is the main season for planting out new strawberries. It’s usually recommended to use the same spot for no more than thee years because of disease build up. First year plant one plant per 30 sq cm. Second year keep the runners that have been sent out. Third year remove the first years runners. Fourth year move to strawberries to an area the hasn’t grown strawberries for at least three years and prepare the soil well by digging in compost and animal manure.
Tamarilos – Ripen around this time and are ready when they have a good all round colour or have dropped off.
Green Houses/Glass Houses for May New Zealand Gardening –
Reduce the ventilation openings to keep in more warmth over night. Remove any bolting plants, dead or dying plant matter. Test soil Ph and add lime if it’s below 6.5 Ph. If you’re growing vegies then keep planting a succession of seedlings as space becomes available. You can transplant or sow broccoli, cress, lettuce, mustard, spring onions, peas, potatoes, radish, onions, spinach and radish.
Regular watering is needed to keep the soil moist. Continue controlling snails and slugs.
Pot and Container Grown Plants
Growth is generally slowing down. When tuberous begonias die off you can store them over winter by turning them on their side so they don’t get water as this can rot them. Then in spring ( September ) turn them upright and water and presto then should return to life. Watering is generally reduced as growth reduces or the dormant phase starts.
Dust with a damp cloth or spray and remove dead leaves.
Control any insect or diseases. If you find mealy bugs on the roots, you can submerge the pot into a solution of pesticide to kill them.
Ornamental Garden for May New Zealand Gardening
Flower seeds that can be sown:
In Northern and central temperate climate – ageratum, alyssum, aquilegia, arctotis, bellis, calendula, candytuft, Canterbury Bells, carnation, cineraria, cornflower, cyclamen, delphinium, dianthus, everlasting daisy, forget-me-not, gaillardia, godetia, gypsophila, hollyhock, honesty, impatiens, larkspur, linaria, livingston daisy, lobelia, lupin, french marigold, mignonette, nemesia, nemophila, nigella, painted daisy, pansy, polyanthus, Iceland poppy, primula, scabiosa, snap dragon, statice, stock, strawflower, sweet pea, viola, Virginian stock, wallflower.
Plant seedlings of: ageratum, alyssum, aquilegia, arctotis, bellis, calceolaria, candytuft, calendula, Canterbury Bells, cineraria, cornflower, cyclamen, delphinium, dianthus, everlasting daisy, forget-me-not, gaillardia, godetia, gypsophila, hollyhock, honesty, impatiens, larkspur, linaria, livingston daisy, lobelia, lupin, french marigold, mignonette, nasturtium, nemesia, nemophila, nigella, pansy, polyanthus, poor mans orchid, iceland poppy, primula, scabiosa, snap dragon, spider flower, statice, stock, strawflower, sweet pea, verbena, viola, Virginian stock, wallflower.
In cold southern climates –
Gypsophila, french marigold.
Bulbs tubers and perennials for May New Zealand Gardening-
You can plant – African daisy, anemone, arctotis, arum lily, aster, bellflower, camomile, candytuft, carnation, chrysanthemum, coreopsis, cyclamen, daffodil, delphinium, freesia, gazania, geranium, hyacinth, iris, ixia, jonquil, lachenalia, lilium, lily of the valley, muscari, peony rose, phlox, polyanthus, ranunculus, rock rose, rudbeckia, statice, sweet william, tritonia, tulip, verbena, viscaria, watsonia, winter primrose.
Dead heading
Remove old dead heads ( flower heads with no petals ), to encourage the production of more flowers or to settle down for winter dormancy. If you want to collect your own seeds, wait till the seed heads go brown then pick and dry them, then crush the head to release the seeds, label them and store them in a paper bag in a dry location until ready to sow.
Herbaceous Perennials for May New Zealand Gardening – When they’ve finished flowering they can be trimmed back. Many can also be divided up and replanted else where.
Roses for May New Zealand Gardening
If you’ve started a spray program it’s best to continue spraying regularly as the weather permits. Remove any dead flower heads unless it’s a once only flowering rose and you want the hips for decoration or jam. The quickest and simplest method is to twist the seed heads off with your fingers, but the best way is to use secateurs and cut back to the next growth bud.
Remove weeds, while they’re small.
Trees and Shrubs jobs for May New Zealand Gardening
When the soil is moist from rain you can plant trees and shrubs. Plan where and what you will plant. Prepare the soil before it gets water logged with winter rain.
Lawn jobs for May New Zealand Gardening.
In warm northern districts lawn seed can be sown. You will need to keep the soil moist. It’s a good idea to rotary hoe areas where new grass is to sown to provide a good depth of loose soil for new roots.
Mow existing lawn as required depending on the growth. The grass should be between 20 to 25 mm after you’ve cut it.
Compost jobs for May New Zealand Gardening tips
Turn your compost heaps so organic matter gets evenly decomposed. Continue building heaps and when they consist of predominantly unrecognisable matter they are ready to be spread around bare soil as a mulch, or dug into the soil.
Make new compost heaps by incorporating dead leaves, grass clippings, vegetable scraps with a sprinkling of lime and animal manure etc.

A blaze of Autumn colour!
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Happy Gardening for May New Zealand Gardening.