What to do in the garden this week Take rosemary cuttings
Fight colds with vitamin C
I’ve booked my flu jab, but another key defence against winter colds and chills is to crank up my vitamin C consumption – and not by taking pills from health stores.
The most obvious homegrown source of vitamin C is citrus fruit, and with the first mandarins starting to ripen, we don’t have long to wait for the onslaught of zesty citrus. If you haven’t done so already, give your trees their autumn ration of specialist citrus food and don’t let up on the watering yet. Keep your trees well-watered with a soak twice a week. If conditions are too dry, the fruit could simply drop off.
If you planted new citrus trees last winter, thin the fruit now too. You do need to be ruthless with this task so that the tree can concentrate its energy on building a strong root system. It’s always hard to knock off perfectly good fruit, but think of it as an insurance policy for good harvests for many years to come.
Citrus trees are subtropical but you can protect them with frost cloth, or use the organic wax-based Liquid Frost Cloth (also sold as Vaporgard). Spray this over the foliage every six to eight weeks. It’s worth getting on with this task now if you live in an area where early frosts can strike.
By planting a selection of citrus trees in milder areas, it’s possible to harvest citrus almost year round. The easiest citrus tree for New Zealand gardens is the hybrid ‘Meyer’ lemon. It’s relatively hardy (compared to true lemons) and very prolific. In Auckland, trees have fruit for 11 months of the year.
Tahitian limes can be slow and shy to fruit but given how expensive limes are to buy, they’re still worth it. The fruit starts to ripen next month.
If you’d rather drink your vitamin C, plant tangelos, navel oranges (for winter fruit) or ‘Harwood Late’ or ‘Valencia’ for spring and summer.
Start spring early
Hyacinth vases are available from garden centres, or you can upcycle a jar with a narrow neck. Select hyacinth bulbs that are firm and show no signs of fungal disease. Fill the vase with water to just below the bulb (it will rot if it’s touching the water). The roots will grow down into the water. Top up the water as necessary. If you like, add a quarter of a teaspoon of florist’s cut-flower food to provide nutrients as the bulb grows. Place the vase in a cool, dark spot for eight weeks (the fridge is ideal) to allow development of the flower bud.
After eight weeks, when the roots have developed into the water and the shoot is around 4cm high, bring the vase out into a dimly lit place. Then slowly (over a period of three weeks) bring the vase into stronger light and a warm position (not more than 18C). This needs to be done gradually as too muchwarmth will cause the hyacinth to flower before the stem is a good length. After you have forced any bulb, you can plant it in the garden, but it will take a couple of seasons before it flowers again, if at all.
Hyacinths are also easy to grow in pots. Plant them any time between now and May and they will flower in August or September. For best results, use a special bulb mix such as Daltons Premium Bulb Mix. You can cram them in as tightly as you like (just make sure they’re not touching). Keep them in a cool shady spot to allow for good root development and water them occasionally to keep the top of the soil moist. Once shoots emerge, bring them into a sunny spot.
You can also grow hyacinths in the garden. Plant them in a sunny spot where there is good drainage at a depth twice the height of the bulb. Creeping rosemary is a great plant for covering walls or cascading over garden edges. Several of my plants got in the way of plumbing excavations and need to be replaced. Luckily creeping rosemary and the erect varieties can easily be grown from cuttings. Autumn is a good time for taking semi-ripe cuttings. These are a type of softwood cutting taken at the end of the growing season when the stems are more mature and less likely to wilt than cuttings of soft stems taken earlier in spring and summer.
Look for new season’s growth and snip off 10cm sections (make sure the stem is hard at the base). Remove the leaves off the lower half and dip in rooting hormone if you happen to have some handy.
Then poke the cuttings into pots of seed-raising mix with a handful or two of horticultural pumice added for better drainage. Several cuttings can go into the same pot, but leave space between the cuttings so it’s easier to separate the roots when the time comes to transplant them.
Roots should form fairly quickly, however cold weather will slow them down, so don’t delay. Other shrubs that can be propagated the same way include salvias (including culinary sage), hebes, penstemons, lavender, viburnum, choisya, and box.
Check on your stored garlic
Just like stored seeds, garlic bulbs can go bad if moisture gets into them. This can be caused by incorrect curing or storing them in less than ideal conditions. Garlic that showed signs of rust before harvest is especially likely to collapse in a cloud of fungal spores during storage.
Garlic will keep for up to eight months if stored well and the optimum temperature for this is between 15-18C. High temperatures and humidity will turn it rotten in no time. So check your bulbs and move them if need be, ensuring they also have adequate air circulation.
Mesh onion bags are a cheap and effective way to keep garlic if you didn’t plait the stems into picturesque braids. Hang the bags from a beam to keep them out of the way and to allow air movement from all directions.
Tidy up your bramble patch
With the exception of a few autumn raspberries, most brambles will have finished fruiting and can be tidied up for the season. This means removing all fruited canes and selecting the best new wood for next summer’s berry crop.
Raspberries are particularly adept at colonising sites via underground stems, sending up canes all over the garden. This silent expansion can quickly get out of control so it definitely pays to keep the bushes contained and in check.
A vast berry thicket may indeed produce more fruit than a nicely managed row of canes but most of it will be painfully out of reach. Unless you have a lot of room and fondness for bramblewrangling, autumnfruiting raspberries are best for backyard production. Summer varieties certainly produce sweeter fruit but they’re usually smaller, less copious and borne on insanely vigorous plants.
Other brambles – especially blackberries and boysenberries – prefer to get around by putting down roots wherever their very long canes touch the soil. This is a great way of getting new plants to increase your stock or give away.
Simply bend the canes down to the soil and place a brick over a couple of the leaf nodes. Roots will grow over the winter and the new plants can be cut loose from the parent cane and transplanted when growth resumes in spring.