The majority of our palm trees are intended to be planted outdoors. Whilst planting palm trees is a relatively easy affair there are a few things to be aware of.
Where to plant palms
Give thought to the eventual size of the palm you are buying; beware of planting large palms too close to buildings or under power lines. Consider also the requirements each palm has. Which direction is the prevailing wind? Is the location wet or dry? Is it shaded or in full sun? When purchasing we can advise you on the most appropriate location for your palm.
When to plant palms
This is probably less of a consideration in Auckland and Northland’s mild and wet climate than in other parts of the country. For milder parts of New Zealand there’s not really a wrong time to plant a palm tree. However a few considerations:
If planting in late spring or summer then do be mindful of drought and water regularly if required.
Autumn is an excellent time to plant since rainfall tends to be higher than in summer and the temperatures are a little cooler.
With the exception of very tender palms there is nothing at all wrong with planting in winter. Provided the ground’s not too boggy your palm will have a good chance to acclimatise before the weather warms up.
Early spring is also an excellent time to plant. If the palm is a delicate species the leaves may look slightly damaged as it will have been growing in a pot outside throughout the winter. However the good news is that you should have an attractive palm by later summer.
In cooler parts of the country with regular exposure to frost and chilly winds it is preferable to plant palm trees after the chances of a hard frost have passed and the ground has warmed up (perhaps late September or early October) through to early autumn (maybe late March). Outside of this period planting is not impossible but palms should be given protection from strong, cold winds.
Soil considerations, drainage and irrigation
The type of soil you have should be taken into account when planting palms. Clay-based soils have a tendency to become waterlogged in winter whilst in summer they can become hard and prone to cracking. Meanwhile sandy soils tend to have excellent drainage but can dry out quickly. In both cases conditioners may be added to the soil.
The two main considerations will be drainage (clay soils) and irrigation (both clay and sandy soils). If you’re unsure about the quality of your drainage try digging a hole and filling it with water. If the water takes some time to drain away (or, worse still, doesn’t drain away) then drainage could be a problem for you. Whilst a few species of palms do enjoy wet feet few palms will grow in stagnant water. There are two options here; if you’re on a sloping section try digging drainage channels to reduce the problem or, perhaps easier, build upwards. Here you will need to bring in additional soil and, perhaps using some form of retaining, create a garden above the water level. Not only will your plants be free of the stagnant water but their roots will be warmer (meaning faster growth in spring), the soil will probably be of a better quality and the palms will appear taller since they’re in a raised bed.
As for irrigation, the simplest approach is to use a basic and inexpensive garden irrigation system. Remember that it’s better to provide infrequent, heavy watering than a light daily watering. This will avoid the palms only producing shallow roots and being dependent upon near-constant watering. Of course the amount of water required will be a function of the species you select. Naturally, large desert palms will need less watering than palms from rainforests.
Preparing the hole
Dig the hole about six inches wider than the pot all around (that is, one foot wider than the pot). Similarly, dig the hole about six inches deeper than the pot. Break up the soil you removed and, if you wish, add any soil conditioners. Re-fill the bottom of the hole to the required depth. Pack the soil down and water well.
At this point you may decide to raise the palm slightly (perhaps one-third of the pot height) or plant the palm so that the soil height is flush with the surrounding ground. If raising the palm be sure to mound sufficient soil around the palm so that it is sturdy and the roots are not exposed. If planting flush with the ground be sure not to over-plant and bury the trunk (this can prove fatal if too much of the trunk is covered).
Removing the palm from the bag or pot
Here you need to be careful not to disturb the roots of the palm. It may be that the easiest way to remove a large palm is to cut the bag or pot. Do this vertically in three places (120° apart) and then cut around the base. For the base itself you may need to cut around the drainage holes if roots have formed tangled knots.
Planting the palm
Carefully place the palm root ball into the hole. Check that the trunk is vertical and that the most attractive side faces the observer.
Filling in the remainder of the hole
Tip in the soil around all sides of the hole. Use a mallet to pack it in so that it fills about half the depth of the hole. Water in well ensuring that the root ball is well watered. Next continue to fill in the remainder of the soil. At this point repeat the watering-in but with a slowly dripping hose for around twenty minutes. You may wish to put garden mulch over the soil to retain moisture.
Continue to water regularly (every few days depending upon weather conditions) for a couple of weeks then reduce to once or twice a week (again, depending upon the weather).
There is no need to fertilise the palm for the first two months. When fertilising we recommend a combination of fast and slow release fertiliser with application in spring, summer and early autumn.
Once established the attractive leaves on the palm are unlikely to be the ones it was planted with. These will usually be cannibalised by the palm to provide the nutrition needed to produce new leaves. This is another good reason not to be overly concerned about the condition of the leaves of a palm before it is planted (other than to ensure that the palm is healthy).