In the garden 01/01/2010

  • If you are making only one New Year’s gardening resolution, for long term gains resolve not to let weeds go to seed. Long term it is labour saving. The light rains this week will have given enough moisture to start the next round germinating. Get them early with the push hoe. If you have ignored the last round and they are setting seed now, weed with a bucket at your side or you will be spreading the seed. Unless your compost heap generates high temperatures (and the black plastic types rot the contents, rather than sterilising by heat), keep seed heads out of the compost. You can either put them out in the rubbish (hopefully they get buried so deep in landfill that they can not germinate there) or if you don’t have rubbish collection, putting them in a black plastic rubbish bag in full sun should work.
  • Do not delay on dividing the autumn flowering bulbs which will be triggered into growth soon. These include nerines, belladonnas, colchicums (often called the autumn crocus), most ornamental oxalis and cyclamen hederafolium. The rejuvenated clumps will reward you soon enough.
  • Flowering cherries are summer pruned to avoid the effect of silver blight. If you have a tree with witches broom, you will have noticed in spring that you had sections which did not flower and where the foliage was much denser and came while the rest of the tree was flowering. Cut out the witches broom before it takes over the entire tree (which it will over time) because then you will have to cut out everything.
  • If you had a problem with silver leaves on rhododendrons last year, check for fresh infestations now by looking underneath the leaves. The problem is leaf sucking thrips. The adult thrips are black and thread-like while the youthful offspring are white. The usual approach is to blast them with a systemic insecticide which the plant sucks into its circulation system. If you are not at all keen on this approach, cut out weak and badly infested plants (the damage won’t be showing in the new leaves yet but it will happen), and open up around other plants to increase air movement. Theoretically, an oil spray will suffocate the little critters and you can use a mix of light cooking oil with a squirt of detergent mixed with warm water. However, the problem is that you have to spray directly onto the underside of all leaves because it will only suffocate on contact so this is only practical where you have a very small number of plants. We haven’t tried them but apparently the collars of insecticide wrapped around the trunk can work well. The DIY approach is to secure a band of carpet around the trunk and then inject the concentrated systemic insecticide into the carpet. Wear gloves.
  • Garlic can be harvested when you think it has reached a good size. Lift it and leave it on the ground while the foliage dies off. After being given a large bulb of smoked garlic at Christmas, we are keen to try smoking some of this year’s crop to see if it extends its shelf life through the season. Garlic tends to lose its oomph after about six months. The smoked garlic is wonderful for aioli and summer dressings.
  • Unlike garlic, you have to wait for the tops of onions to bend over and start to wither before lifting the crop.
  • Keep successional sowings of sweet corn, lettuce, salad veg and beans going and in a warm spot, you can plant a late crop of tomatoes.