January is hot and humid with high rainfall. This creates ideal conditions for pests and diseases to wreak havoc in the garden. Be observant and react as soon as any problem is detected. Plant growth is rapid and often needs to be checked with light to heavy pruning. Weeds are also a constant challenge as they grow with such vigour.


  • Feed and water annuals and perennials regularly through the hot weather.
  • Deadhead spent flowers to encourage prolonged blooming.
  • Water hanging baskets and containers regularly, especially those placed under overhanging roofs and dense tree canopies, where rainfall doesn’t penetrate.
  • Stake dahlias as they come into full bloom.
  • Sow seeds of primulas, poppies, pansies, foxgloves, aquilegias and delphiniums, along with many other cool season plants. These are all important spring garden flowers.
  • Continue planting out young plants of summer and autumn flowering annuals. It’s still too early for winter seedlings. Portulacas, dianthus, salvias, zinnias and vincas are good options at this time.


  • Keep tomatoes well staked, along with peppers, chillies and egg plants.
  • Protect cauliflower from sunburn by breaking and placing the leaves over the curds.
  • Make final sowings of bush and runner beans, maize and sweet corn, gem squash and courgettes. In warmer climates these vegetables can be grown through most of the year.
  • Check for aphids and cabbage caterpillars on brassicas (cabbage family).
  • Harvest ripe vegetables on a regular basis. Freeze the surplus produce where possible.


  • Many herbs battle to survive in the heat and humidity at this time of the year and need to be cut back or replaced.
  • Mint grows vigorously and it’s a good time for it to be pruned back and fertilised.
  • Plant more sweet basil plants out now, so they’ll be ready for the autumn months.
  • Sow regular crops of coriander, rocket and mustard on a monthly basis.
  • Cut back and divide chives, garlic chives and spring onions.


  • Get rid of all fruit that has dropped from the trees by burying it, rather than throwing onto the compost heap.
  • Many different types of fruit are ready for harvest at this time of the year – from mangoes and figs to early apples, peaches, nectarines and plums.
  • Summer prune fruit trees like peaches, nectarines, apricots and plums that have finished cropping.  Get rid of broken branches and twigs caused by fruit and harvesting.
  • Tidy up strawberry patches. Discard old, unproductive plants and re-plant with stolons (plant-lets that form on the runners of mature plants).


  • Apply a deep mulch of acid compost to the root zones of camellias, azaleas and hydrangeas.
  • Prune off spent flowers on hydrangeas and early flowering perennials like agapanthus.
  • Check for lily borer caterpillars on crinums, agapanthus, clivias and other members of this plant family. Treat immediately if you come across any signs of infestation.
  • Prune back Acanthus mollis to ground level and mulch with compost to promote new growth.
  • Tidy up the dead or dying leaves on bulbous plants like watsonias, kniphofias, dieramas and zantedeschias (arum lilies).
  • Divide bearded irises immediately after they finish flowering. Remember to add lime to the newly prepared soil. They enjoy alkaline soils.
  • Colourful filler plants for planting out now are – angelonias, dahlias, euphorbias, gaura, impatiens sunpatiens and begonias.


  • Carry out a light summer pruning by removing dead wood and straggly growth on rose bushes.
  • Dead head spent flower stems.
  • Water roses deeply during dry periods, preferably in the early morning or evening.
  • Continue fertilising using your annual feeding programme. 8:1:5 or 5:1:5 fertiliser formulations are recommended.
  • Spray every 10 to 14 days against fungus and insects. Use a wetting or sticking agent for greater efficiency.
  • Pay special attention to red spider mite infestations on the under surface of leaves, especially the older ones.


  • Mow regularly, as grass growth is extremely vigorous at present.
  • Remember to collect the lawn clippings and add them to the compost heap. Do not scatter them around the garden whilst they are green.
  • Trim lawn edges neatly.
  • Continue fertilising with a high nitrogen fertiliser like LAN. Water immediately after application.
  • Spray for broad leaf weeds that are in full summer growth.


  • Check vigorous creepers and climbers like wisterias and petreas and cut back any really aggressive growth.
  • Trim topiaries and hedges more frequently during the summer.
  • Mulch trees and shrubs to reduce water requirements and keep root zones cool. Pine bark or well-rotted compost work well as a mulch.
  • Apply snail and slug bait regularly to the relevant parts of the garden.
  • Weeds throughout the garden are a major summer challenge, especially after the festive season. Consider using a chemical herbicide where applicable to check the aggressive growth at the moment.

Rest is not idleness, and to lie sometimes on the grass on a summer day listening to the murmur of water, or watching the clouds float across the sky, is hardly a waste of time.


DISCLAIMER:  The information presented on this website is intended solely as a general guide. We neither endorse specific plant varieties over others nor claim expertise in stock performance. All information is believed to be accurate, based on private inquiries and experiences, and is provided in good faith. Blackwood’s, including its employees, disclaims any responsibility for harm, loss, cost, or damage arising from the use or reliance upon any information on this website, especially if any part of the information proves to be inaccurate or incomplete. Please note that the displayed photos are not representative of current stock but are used for illustrative purposes only.