Header image: Sam collecting Festuca seed in the high country

News from the nursery and autumn outlook

After a long dry summer, the autumn rain has begun and the conditions for planting are looking good, with the next 3 month outlook suggesting temperature, rainfall and soil moisture to be near average, with a good chance of temperature and rainfall being above average, though NIWA does admit the rainfall forecast confidence is low as “the models have not performed well for rainfall over the past few months.”

Above: Griselinia littoralis cuttings in one of our cutting beds

We’re keeping up potting and propagation over the autumn, finishing the last of the seed collecting and getting everything ready to slow down over winter.

Above: Festuca seeds collected in the header image become pricked seedlings in cell trays in our prophouse

Community planting days

If you’re looking to get some planting time in this autumn while also helping out the local environment you can participate in one of the upcoming planting days organised by our local planting groups. If you’re in Cromwell, the Mōkihi Reforestation Trust is doing good work at their three keystone sites and you can help out May 3 at the community planting day at Richards beach. Richards beach site is an iconic and historic site, the scene of much gold digging by the early settlers, and much transformed by Mōkihi as the below pictures show. With some imagination, you can imagine in a few more years how this site will be a thriving native plant community and an even more stunning place to go for a walk.

Above: Richards beach planting site before and after planting, with invasive pines and other weeds removed

If you’re in Queenstown, the next Whakatipu Reforestation Trust community planting say is also May 3 at the Lake Hayes Pavilion to continue their project replanting the margins of the lake, important work to improve both water quality and bird habitat.

Everyone is welcome at these planting days regardless of age or experience and it’s a great way to get involved in ecological restoration and meet some like minded individuals!

When is the best time to plant?

One of our most frequently asked questions is “When is the best time to plant?”. Traditionally our two planting seasons in Central Otago are spring and autumn. Both have their advantages, but spring gives you the most growing time possible before winter, while autumn gives plants the best chance to get roots established while the soil moisture levels are high, minimising drought stress. If planting in summer, irrigation is recommended.

The answer to the question could be different for every person, plant and project, but generally we prefer autumn for planting. This is because where we are, summer drought is both the main limiting factor for growth and the biggest risk for plant survival. By planting in autumn, plants are given as many good growing days as possible before summer comes back around. The hope is that by that time roots will have grown deeper into the ground where the water will remain in summer. We tend to plant from April after a few good downpours as the ground is moist enough for planting, while still holding enough warmth for roots to grow. Warm autumn soils will facilitate good root growth, more than in early spring. Plants generally need temperatures of 10 C or above to grow roots and shoots.

With that said winter and spring are viable times to plant, despite less time for root growth before summer. Due to the cold temperatures of winter and early spring plants planted in these seasons will be dormant but the plants will be in place for when the temperatures rise and growth begins. There are times when spring planting is preferred over autumn planting, for example, when planting species where frost tolerance is a concern. Many plants bought from nurseries and garden centres are young - young plants tend to be less frost tolerant than after they are established. Thus, if the plant species is on the margin of being able to tolerate frost in the planting site it may be a good idea to plant in spring so it has the longest time possible to get established by the following winter. Furthermore, plants from garden centres are often shipped from areas with different climates and need weeks or months to acclimatise to a cooler climate.

Without this time to develop hardiness, the risk of succumbing to frost is higher. The risk is reduced if these plants are planted in spring after the hard frosts have passed (generally October - November). If plants are grown locally in the same climate as the planting site then this is not a problem. Spring plantings may need more irrigation than autumn plantings to grow over the dry season, but irrigation requirements depend on the site, plant choices and planting treatment.

Autumn berries - creating a platter for birds

Days are beginning with a crisp chill in the air, dew is a regular occurrence and the day ends in warmth. Autumn continues with echoes of summer lingering on. Summer flowers fade, but they are replaced by a plethora of different shapes, sizes and colours of fruit. This fruit provides a veritable larder for birds and lizards going into winter.

Many native shrubs have small or even indistinguishable flowers and understandably get passed up for plants with large flowers attractive to humans. However these shrubs that could be described as unexciting are transformed in autumn into beaded jewels. Coprosma propinqua is ubiquitous in the high country shrubland and usually doesn’t get a second glance but in autumn they are laden in shiny drops of blues, whites or yellows. Cordyline australis are adorned with glistening pendants. Corokia cotoneaster, usually reserved and blending into the schist, flames to attention with bright red, orange or yellow fruit.

Above: Coprosma heavily laden with fruit in late February

When considering animals that eat fruit in New Zealand birds are the first that spring to mind. Lizards, however, are also frugivores and important seed dispersers -especially in arid ecosystems. One study found at least 8% of a southern grass skink’s diet was made up of Coprosma propinqua berries and lizards accounted for 45 - 95% of predation on the fruit (Wotton et al, 2016). Most lizards, like skinks, are much more visible scuttling on the ground in stony tussock country so it is understandable to be oblivious to lizards in the bushes. Lizards with the ability to climb like the Kawarau Gecko, Woodworthia “Cromwell”, are nocturnal, making them less observable to us diurnal humans. Shrubs with berries that feed skinks often have their berries on the inside of the twiggy branches where skinks can dine with protection. Plants that cater to lizards are rewarded by having their seed deposited in protected rock crevices which collect moisture - prime real estate in dry eco systems.      

Above: Coprosma growing out of cracked schist tor in prime lizard habitat

It is thought that berry colour plays a large part in attracting the favoured disperser (Lord & Marshall, 2001). Colours like reds, yellows, oranges, blacks and purples are said to attract more birds whereas blues and whites attract lizards. Melicytus alpinus, Muehlenbeckia axillaris, Coprosma acerosa or Coprosma brunnera with their white or blue fruit will be perfect for feeding lizards. Fuchsia excorticata, Melicytus ramiflorus, Podocarpus hallii, Pseudopanax colensoi and Coprosma lucida are just some that could be included in planting for birds.

It is important to plant a diverse range of fruiting plants as fruit will ripen at different times through the season. Having a variety will create a continuous food source. While the purpose of a bird's diet in summer might be to reproduce, in autumn it is to survive the lean winter. In autumn and winter the proportion of fruit in a native bird's diet increases, becoming a main food source. Whilst most berries are produced in March and April many plants produce berries at different times throughout autumn and winter. Birds have been found to have preferences for different berries. Some berries like those of Corokia cotoneaster won’t be touched until all other berries have been consumed. These late berries will provide a vital food source for the hardest time of the year.

Above: Corokia berries in mid April

Plant troubleshooting and spotlight

A low growing tight hedge is a classic part of a formal garden and remains popular today. One common problem with English box hedging, Buxus sp, in this environment is discolouration caused by too much sun to a plant that is not acclimatised to full sun. You can see the typical pattern of this discolouration in the picture above.

This is nothing to worry about unless it progresses to a point where the leaves are completely yellowed or falling off. The new growth in spring will be a fresh green and cover the discolouration, and as the plant gets more established it will be acclimatised to the environment and will not yellow off in future.

Discolouration in box hedging can also be caused by insufficient nutrients and water in the soil. You can fix this by improving soil with mulch, blood and bone.

We’re happy to troubleshoot any other problems you might be having with your plants, so if you are looking for advice, please do get in touch.

If you want a formal hedge but want to avoid the down sides of the slow growing Buxus, we have some very bushy Lonicera available in the PB6.5 grade. These are very versatile and tough plants that can be clipped to a hedge of any size or shape.

Lonicera nitida PB6.5

$10.50

Common/Maori name(s): Box Honeysuckle

A fast growing hedging shrub growing between 40 - 60cm per year. Can be used for hedges up to 3m in height. The small dark leaves result in a very neat looking hedge when clipped. This plant can be grown in full sun or part shade in all soils apart from very boggy soil. Very hardy to frost down to -20c. Drought tolerant but not tolerant of very high wind. If unclipped or infrequently clipped it will bear purple berries in late summer / autumn eaten by birds. In spring the lightly fragrant flowers are very sought after by honeybees.

Height of grade at sale: 30cm

As always if you are planning any plantings or big jobs for this autumn or next spring let us know and we will prepare a quote. The more lead time you can give us, the better we can meet your needs.

Check out our Catalogue for more information or feel free to flick us an email or a call.

As always, if you want a quick overview of what we have immediately available in stock, you can check our order page.