July – September: key months for garlic success!

Jun 23, 2024 | Gardening tips, Garlic

Now that the shortest day has passed, garlic planted in the autumn will have developed a strong root system and healthy green shoots but what next? How do we support the swelling of the bulbs into good-sized, healthy heads? Action taken from July to September is key to success.

Bulb swell occurs as days lengthen and temperatures rise. This happens progressively after the shortest day (June 21) until heads are ready to harvest in November. However, most of our energy needs to be concentrated on the months of July, August and early September if we are to harvest a great crop.

Weed, mulch, water July – September

  • Weed your beds well and keep them well weeded until harvest – garlic dislikes competition from weeds.
  • Mulch (if you have not already) to a depth of 5cm, preferably with sugar cane mulch, keeping the mulch clear of the stems to prevent collar rot.
  • Begin spraying with diluted Seasol or Maxicrop according to instructions and then repeat every 2-3 weeks. These are seaweed solutions that add minerals and micronutrients, balancing any deficiency in your soil. Note: they do not add nitrogen.
  • Water regularly with either dripline or straight onto the soil. Do not water overhead as this can result in fungal diseases such as rust. Watering must be deep and regular (twice a week generally) but not result in soggy soil. Do not be misled into thinking that rainfall under 10mm per day counts as watering – none of this will penetrate the soil and reach the roots. Garlic bulbs grow best if always moist.

Fertilise in late August to early September

  • Side-dress your garlic with blood and bone. This means pulling back the mulch and sprinkling it (according to instructions) between the rows of plants. Trowel it into the soil surface. Blood and Bone contains nitrogen and this helps bulb swell. However, if you apply it later than early September, it thickens the stems at the expense of the bulb and can cause fungal problems.
  • If you notice that the leaves are yellowing or the plants are weak, spray them with fish emulsion, also a nitrogen product.

Once early September has passed, simply keep your garlic well weeded, mulched and watered, and spray every 3 weeks with a seaweed solution. Two weeks before harvest, stop watering so that the bulbs are as dry as possible when pulled.