Whether you are completely new to gardening or a green thumb from way back, you'll find a lot of useful info here in our Gardening Advice section.

Start with our monthly gardening guide where you'll find seasonal tips for all the things you need to do this month, next month and beyond.

If you're looking for help on a specific topic, try the Gardening Information section and if you don't find what you're after please contact us. We're more than happy to help.

 

Garden Guide for May

The Edible Garden

Blueberries

Blueberries are a much enjoyed fruit. The fruit ripens between December and April. Though often an expensive fruit to buy, as garden plants they are easy to grow and crop well in the home garden. The plants themselves are quite decorative. For maximum cropping potential plant two different varieties.

March, April, May
Citrus

Time to plant citrus; citrus fruit grows well around Whanganui and can also be grown successfully in large pots. They are generally easy plants to grow requiring little or no pruning they usually do not succumb to insect pests therefore do not need regular spraying.

Time to do a health check up on your citrus. At this time of year they should be laden with fruit which will ripen through the winter months. As the plants energy reserves go into the fruit development the leaves often turn yellow at this time of the year. It is recommended to fertilise citrus trees, including lemons, limes, mandarin’s etc with ‘Tui Citrus Food’ at this time. Additional to the citrus fertiliser a side dress of Epsom salts is also highly beneficial. A healthy well fed plant will not only provide a better harvest but will also be far more resilient against pest and disease attack.

Fertilise lemon trees and other citrus now using ‘Tui Citrus Fertiliser’, this will help with fruit development and the general health of the tree.

April, May
Garlic

Time to plant garlic. Seed bulbs are in stock now in the garden centre. Pull off the individual cloves (there's no need to peel them) and plant 10-15cm apart and 5cm deep. Plant garlic bulbs in free-draining, moist but never waterlogged soil with the pointy ends facing up.  To try some thing different grow some elephant garlic, they are sold as individual cloves that will grow to form huge bulbs.

For more information on Garlic follow this link

April, May, June
Harvest feijoa

Harvest time for feijoas, the fruit is ripe when it falls on the ground. If you want to grow feijoas then planting two or more will increase pollination and fruiting. A clever method is to plant different varieties with timing of harvest of early, mid and late, this will give you a fruit harvest from mid-March to late May.

March, April, May
Plant lettuce

Plant lettuce varieties in pots or the garden in a sheltered situation where heavy frost will not cause heads to rot, try coloured fancy varieties in pots for edible colour!

April, May
Preparing the site for a new vegetable garden

Vacant ground can be dug over and fertiliser and/or compost added to it. This is the best time to add lime to the soil in your vegetable garden. If you garden on heavy clay soil the lime helps to combine with the very fine particles of clay soil to form into larger particles that are more easily cultivated.

April, May
Sow broad beans

Broad beans are a cool season crop and it is time to sow them now, with a second sowing in June or July as a successive crop. They are normally ready for eating in 16 weeks. They are best grown in full sun in well dug soil and sheltered from the wind.

We highly recommend the ‘Chefs Best Ican Broad Bean’ called Mr Green Seed. It will produce a great crop of beans that look good and taste good. Mr Green Seed produces beans that remain green after cooking. Rich in minerals, vitamins A & C, and dietary fibre. Broad beans sown now will give you heavy crops of delicious beans in late winter and spring.

April, May
Strawberry planting

The best time to plant strawberry plants is during May & June. While strawberry plantings can be made year-round, planting done in the cooler months tends to result in heavier cropping than plantings made in warmer months. If they are planted too late, i.e. closer to the longest day (December), they will tend to produce an abundance of runners instead of fruit. So plant now to have lots of strawberries for Christmas!

A variety that has had much success with gardeners in Whanganui is Camarosa. This strawberry produces large firm berries with a medium-red colour. The flavour is excellent and the fruit is relatively resistant to wet weather.

The Strawberry variety Camerosa will be available as bare root bundles some time during May for a very limited time (approx. 5-7 days) and Albion later in the month. If you want to buy a reasonable quantity of plants then you are best to place an order to ensure you don't miss out! Otherwise they will be available later in May in pots and punnets.

There seems no limit to how and where strawberries can be grown, and they are fairly fool proof that anyone can plant them and be rewarded with fruit! They can be grown in old car tyres where the heat of the tyres hastens ripening, grown in hydroponics, in glazed or terracotta pots, specialist herb/strawberry planters, hanging basket or they can fit in the herb garden. Some grow them along the edge of a vegetable garden and others will dedicate a spot to mass produce their favourite berry!

For more information on Strawberry planting follow this link

May, June
Winter Vegetables

With a bit of forward planning you could have a nice crop of winter vegetables to harvest during the cold months. Planting these vegetables now will get the vegetables as close to maturity as possible before winter really sets in.

Plant out silverbeet, spinach, cabbages, cauliflower, broccoli, broccoflower, spring onions, brussel sprouts, beetroot, celery, lettuce & and pak-choi. At this stage of the year with the lead up to winter shortening, seedlings are best planting choice.

However sugar snap peas, carrots, swede, turnip, and raddish are best sown as seeds. Plant these seeds directly in the garden.

If you have an unused bean frame consider growing sugar snap peas which can be eaten pod and all. These do well during the winter months and are easy to grow. A top pea variety is Pea—Magic, It is part of the ‘Chefs Best Ican’ range and produces dark green pods on vigorous high yielding plants. It boasts a good resistance to fusarium and powdery mildew which means you keep on picking till the last pod is produced.

March, April, May

General Tasks

Best time to plant a tree

Autumn is the best time of year to be making plantings of trees and shrubs so that they can establish good root systems before the dry of next summer. They often make far bigger, better and stronger plants, more quickly than those planted in the spring. Why not plant some fruit trees? Home grown fruit tastes better and is alot fresher.

March, April, May
Compost leaves

Great time to make compost! Gather up falling leaves, layer the heap to include shrub prunings, grass clippings (not too many), vegetable scraps, garden weeds etc. Be sure not to make any layer excessively thick. This will rot into the most excellent mulch to use in the spring. Add ‘Reln Garden Worm Farm & Compost Conditioner’ or ‘Tui Garden Lime’ to the pile to speed decomposition.

April, May, June
Frost preparation

Prepare for frosts; make sure you have supplies of frost cloth ready if you have frost sensitive plants that may be at risk. You can also spray on a product called vapour-guard which will give frost protection to treated plants.

May, June, July, August
General Maintenance

Time to catch up on garden maintenance including; lawns, edges, weeding, pruning trees and shrubs and removing things that are past it.

May
Grass grub in lawns

Treat grass grub problems in the lawn at this time of the year. Grass grubs eat the roots of the grass causing the tops to die. This results in brown patches developing in the lawn and birds digging at the surface as they look for the grubs. At this time of the year the grubs are close to the surface and can therefore be effectively controlled. ‘Yates Insect Killer for Lawns’ should be sprinkled over the lawn surface around affected areas prior to or during heavy rain. Alternatively, ‘Yates Complete Lawn Insect Control’ can be connected to the hose and watered onto grass areas.

April, May, June
Protect plants/cloche

Keep an eye on the weather, be prepared to protect young plants with temporary covers (like a cloche) from unseasonable cold or hail storm, strong and cold wind or torrential rain which can strike at any time.

The use of a cloche to cover out newly planted seedlings will greatly increase the growth rate at this time of year.

May, June, July, August, September, October, November
Winter spraying

If you are not keen on spraying but really need to for obtaining good crops on fruiting plants then choose to do winter sprays. This will clean up overwintering pests and diseases and reduce the need for spraying later in the season when fruit is on the trees. Winter sprays on roses will improve spring growth and subsequent flowering.

Lime Sulphur

Very useful in Whanganui to help induce dormancy on deciduous fruits and plants particularly roses. By doing so the plant has a proper rest period & will reward with better blooming in the coming season. Lime sulphur will also remove lichen from plants as well as controlling insects including scale insects & mites. It provides a protective film of sulphur over buds to prevent the entry of fungus into plants and trees. (Note lime sulphur is not suitable for apricots)

Grosafe Enspray 99

An spraying oil for control of scale, mites and mealy bug on fruit trees, grapes, roses and other ornamentals. Applying during the dormant period reduces the pest incidence during the coming season.

Grosafe Freeflo Copper

Freeflo copper protects against fungal diseases including blackspot, downy mildew & curly leaf (peaches & nectarines). Grosafe Freeflo copper is as improvement on other powder & liquid types of copper giving a far more complete coverage and stronger fungal protection

For ease of application mix Grosafe Enspray 99 & Grosafe Freeflo Copper together.

May, June, July, August

The Flower Garden

Cyclamen

Time to grow cyclamen; One of the longest flowering plants that are excellent for pots and gardens are cyclamen. They thrive in pots and well drained shady areas of the garden. They come in a range of offerings including larger growing plants with large flowers and foliage to those with miniature foliage and miniature flowers. A typical miniature cyclamen that you would buy in the garden centre can have up to 200-300 flowers in a season!

Cyclamen can be grown indoors or outdoors in a shady spot. These winter flowering beauties make a room bright & cheerful and are an excellent gifts. There are two types readily available the larger flowered and a miniature type which are usually lightly scented.

May, June, July
Fertilise now

Maintain healthy plants of pansies, primula, cyclamen and polyanthus by fertilising with ‘dried blood’ (different from blood and bone). It can be applied as a powder directly to the soil or mixed with water and applied with a watering can.

May, June
Looking for colour?

Good colour at the moment are many camellia sasanqua varieties. They are in full flower with others in bud due to burst. Other good shrubs or plants for providing winter flowers include:

  • Camellias
  • Ericas
  • Grevilleas
  • Hellebores
  • Primroses
  • Polyanthus
  • Cyclamen

Consider these plants for beautiful foliage colour prompted with the cooler weather.

  • Coprosma
  • Nandina
May, June, July
Pansies are back!

Its pansy planting time! Pansies are the most popular winter flowering bedding plant. They are suitable for sun or shade, pots and gardens. They are a truly good looking, long flowering versatile plant – check out the wide selection available in stores now.

April, May
Rose planting

Time to start thinking roses! New seasons roses varieties will be arriving into the store from the end of May. Roses really are an impressive plant. There are few plants that can boast the growth rate and extent of flowering that a good rose will provide. A rose bush purchased in June or July (that looks like a group of sticks in a pot) will by November will be 60-80cm in height and producing a mass of colourful blooms, most roses (depending on the variety) will repeat flower throughout the summer and well into next Autumn. Prepare the soil for new season rose plantings in preparation for this arrival.

Rose pruning in Whanganui is best left until mid July. Other wise our mild temperatures tend to promote early growth which may be damaged by frosts.

However now is the time to order roses now for winter delivery to ensure you don’t miss.

March, April, May, June
Spray your roses

Towards the end of May it is time to spray roses & fruit trees with Gro Safe lime sulphur to induce dormancy and remove overwintering scale insects, moss and lichen.

May, June
Time to sow Sweet Peas

Now is the time to sow sweet pea seeds for a fragrant and colourful, winter/ spring display. To help germination of the seed, soak the sweet pea seeds in water for several hours, before planting. This well soften the shell of the seed. Plant your seed in a sunny and well drained site

March, April, May
Winter flowers to choose

There is a huge range of flowering plants to choose from, to fill up the gaps in your your winter garden. These include

  • poppies
  • sweet William
  • stocks
  • polyanthus
  • cineraria
  • calendula
  • antirrhinums
  • dianthus
  • lobelia (in frost sheltered spots)
  • kale
  • primulas

to name a few. Plant these flowers to give cheerful colour during the coming months. Come in and check out the range available in the garden centre now.

April, May, June, July