Wally Richards – Christmas Gardening

Firstly we would like to wish all our readers a very merry Christmas and a happy gardening New Year.

We are now halfway through another gardening year with the longest day here.  This is the time of year when our gardens are growing at maximum with only the moisture content of the soil to interfere with plant growth (maybe adverse weather aspects also).

Plant growth relates strongly to the number hours of natural light that plants receive in a 24 hour period. At this time of the year plants receive about 16 hours of natural light where in mid winter they have only about 8 hours. This means at this time, your plants, lawns and weeds are growing at max with the only real restriction being the moisture level in their root zone.

This fact can be used to your advantage if you water most of your preferred gardens by hand where you can apply water to the root zone of your plants, leaving the soil elsewhere dry. Weeds then will only grow and thrive in the moist areas and fail in the dry spots till rain allows them to grow again. Gardeners that use broadcasting sprinklers will have a far greater weed problem than gardeners who water by hand.

Waterproofing your gardens at this time of the year will pay dividends especially if you are going on holiday and have no one to water your plants. This is simple to do and a great way to use up newspaper or cardboard that you have laying around.

Give the area you wish to protect a reasonable watering then cover with either several layers of newspaper or a layer of cardboard, either of which you also wet down. Do this on a calm day to make life easier.

Next you cover the paper or cardboard with a good layer of purchased compost. The reason for the purchased compost is that it will be weed free.  The area thus treated will retain moisture and be relatively weed free for sometime. A third advantage is the newspaper or cardboard will encourage earth worms to populate the area as they just love these materials in their diet.

Further dry proofing of your plants can also be achieved by spraying the foliage of preferred plants with Vaporgard. This is applied to both sides of the leaves and reduces the plant’s water needs by about 30% plus. One spray lasts on the foliage thus treated for about 3 months so that takes us nicely through the hot, dry summer period. The same product can be used on container plants out doors to advantage as it will reduce their water needs also.

Permanent mulches such as weedmat and bark can be very dangerous in wet winters especially on heavy soils that have poor drainage. These permanent mulches prevent the surface drying as should happen with the natural actions of sunlight and wind.  Plants that dislike wet feet will suffer when the soil is covered with a mulch during wet times.

Last winter many gardeners lost plants because of wet soil and mulches which did not allow the soil to dry out quick enough and the roots of the plants rotted. Some of these plants have started to recover but in doing so a certain amount of the foliage has died.
Tidy up the plants leaving the healthy new foliage in tact.

When we experience a wet winter any mulches applied to the soil in the summer should be pulled back away from the root zone of plants in areas where the drainage is not very good….

A number of gardeners who planted potatoes early in the season will now be looking forward to harvesting their home grown new potatoes for Christmas dinner.

A question that I am asked by a number of new gardeners is how do you know when a crop is ready to harvest. The first answer to this is the type of potato that was planted as there are basically three categories, very early, early and late crops which indicate the maturity times that each type has from sprouting and planting to harvest, in average growing conditions.  The times being 60 days, 90 days and 120 days (very early, early and late).

If you know the type and the date you planted the sprouted seed potatoes then the above times will give you a good indication of maturity time.

There also are two other ways to determine if a crop is ready and the first is examining the tops. Very early ones may not flower when they mature but if they start flowering then the crop is ready. Early types are normally ready when they flower. Late crop types are ready when flowering has finished and the tops start to die back. You can always lift one plant to check the potatoes underneath for the number and size of tubers.

If only smaller spuds are found then leave the rest of the crop till the tops start to go off.
For those that want a few new potatoes for Christmas dinner but do not want to harvest the whole plant, you can feel under the soil with your fingers and pull one or two tubers off each plant. The term for this is called “Bandicooting” and can be done after the plants have been in for about 6 weeks or more.

A number of gardeners have complained to me recently that their potato plants are starting to get yellow leaves and the tops are not growing as well as before.
On questioning them further I found that their crops had been in for 2 months or more and likely had reached maturity and starting on the die back aspect. So likely nothing to worry about. Once you have harvested your potato crop you should store them without washing them or in other words, with the dirt still on them. Best stored in a cool shed and kept cool so they don’t start to shoot again too soon. Very early types such as Rocket or Swift do not store well and will quickly go off or start to shoot……

Tomatoes planted before Labour Weekend should have a good numbers of tomatoes on them and starting to ripen. It is important to keep the soil moist and apply tomato food every few weeks as they will keep on growing and producing new flowers and fruit while the conditions are favourable.

Starting off another batch of tomato plants either from seed or laterals can be done now to have younger, vigorous plants growing and producing well into the autumn months.
When removing laterals make sure that the day is sunny and not humid as this is when diseases can enter the wound and plant losses will happen. It is a good idea to have some Liquid Copper made up in a trigger sprayer and to squirt the wound as soon as you remove a lateral or leaf.  Further protection can be applied against die back by applying a monthly spray of Perkfection.

Any problems ring me at 0800 466464 (Palmerston North 3570606)
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5 comments on “Wally Richards – Christmas Gardening

  1. Sue Mark on said:

    Can you compost the spent potato plant in the compost bin?

  2. Hi Sue, You can, however its a good idea to chop it into chips or at least in half. Then again nothing wrong with a self sown crop of potatoes.



  3. dot bryant on said:

    We have a row of camelias, (hedging type), about 15, currently up to up to 1m high, that we would like to move, close by, into prepared beds. What is the best time of year to do this?

    The plants are a mixture of cuspidata hybrids, sasansqua, and japonica

  4. Lisa Quinn on said:

    How do I harvest my own seeds from a courgette plant?

    Also, are there any organic ways to keep caterpillars off brassica plants?

    Any help would be greatly appreciated.

  5. nice

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