Mid winter is the ideal time to re-pot indoor and outdoor container plants, prune roses and other flowering climbers and shift deciduous trees. Here’s a round-up of things to tick off your mid-winter to-do list
Watch out for borer
Keep an eye out for tiny piles of sawdust and small holes in the branches of citrus, kowhai and other trees, which are signs of lemon tree borer. Prune out affected branches or squirt borer spray into holes then plug with pruning paste.
Prune any potted roses
Potted roses need their tops and bottoms pruned for tip-top performance. Take them out of the pot once you’ve pruned their branches and give the roots a light trim. Re-pot with fresh potting mix.
All you need do with climbing roses is remove the branches you don’t want and reduce remaining canes by a third.
Reinvigorate flowering climbers, shrubs and trees
Many flowering climbers, shrubs and trees can also be pruned now for shape or to reinvigorate the plants so they’ll flower better. But leave azaleas, hebe, manuka, flowering cherry, crab apple, viburnum and other plants that bloom in spring until after flowering is finished. It’s easy to cut off flowering stems if you prune them beforehand.
Deciduous trees – ornamental and fruiting – are usually planted in winter while they’re dormant. You can also shift deciduous trees or shrubs now.
Re-pot indoor and outdoor plants
Winter is a good time to re-pot indoor and outdoor container plants. Water the pot beforehand and leave to drain. If the roots are crammed you’ll need to replant into a bigger pot or trim roots. Either way, make sure you remove very long and dead roots. Re-pot using fresh potting mix, making sure the rootball is level with the top of the mix. Gently firm the soil and water well.
When re-potting, make sure to check the drainage holes are clear, especially for outdoor pots. Heavy rain can saturate the potting mix and kill plants if water can’t drain away.
Prune the roses
Sharpen up the secateurs as this month is rose-pruning time – although it might pay to wait until late August/early September in very cold areas. Do the basics (ie remove dead, diseased and old branches) then shorten the branches, making an angled cut just above (about 5mm) an outward-facing bud. Slope the angle of the cut away from the bud so that water won’t run into it. Your roses will love you for it, producing lots of lovely blooms in spring.
Words by: Carol Bucknell