As our season transitions from summer to fall, many changes are occurring in our gardens. Plants are setting seeds and growing more slowly. Our bird population is shifting as migrating birds pass through and our summer birds begin their migration. Even the insect population is a bit different as we have fewer aphids, but many more whiteflies.
Many gardeners are wondering if it is finally cool enough to fertilize the lawn, vegetable garden, and flowers. This would be a good time to add some fertilizer to most things — especially a fertilizer that is not too heavy on the nitrogen, which can cause lots of new tender growth. This means a fertilizer in which the middle number on the label is the same as or larger than the first number on the label. The first number represents nitrogen, which encourages green leaves and fast growth. What we want at this time of year is more fruit and flowers. The middle number on the label represents phosphorus, which improves the production of fruits, flowers, and roots.
Roses will bloom into November if we do not have an early winter. We can apply another round of fertilizer for the upcoming blooms. We also can add another layer of compost or mulch to cool or warm roots, hold moisture, and discourage weeds. With cooler temperatures, these flowers will bloom again and again.
We can fertilize both warm and cool season grasses again. The lawns will green up now that we have less intense heat. Also, homeowners can cut back on the water, as the grass is not absorbing it as quickly as it does during the summer months.
Now is a good time to fertilize the vegetable garden, to push for more fruit until the end of the season. Again, a high phosphorus fertilizer will encourage the plants to produce blooms and fruit. It also would not hurt to add more compost on the vegetable beds. The vegetables may take longer to ripen, as the days become shorter and cooler, but they will taste great.
We also should apply a slow release or a mild fertilizer to the fruit trees. We do not want to encourage a spurt of growth. However, we want the trees to have the necessary nutrients to develop more roots and prepare for blooms and fruit in the spring.
For more flowers, we can deadhead our perennials and give them a layer of compost to build the soil around them. A dose of a slow release or mild fertilizer may encourage them to set fall blooms as they prepare for the end of the season. Perennials appear to sit in the garden through the winter, though in our mild winters they are busily creating a stronger root system that will take them through the spring and summer bloom cycle.
Shrubs also will continue to build their root systems through the winter. Now is a good time to give them a layer of compost also. Again, a mild fertilizer that is low in nitrogen will encourage root development without pushing too much new growth that would be freeze tender.
Compost, a mild fertilizer and a long, slow soak will be good for our trees as the season winds down. Keep in mind trees expand their root systems year round.
Many of our native plants do not respond well to too much fertilizer, water or a rich soil. Take a light hand when fertilizing these plants.
Compost layered onto the flower beds, garden beds, and lawns adds nutrients and microorganisms to the soil. It also helps the soil hold moisture and retain a more even temperature, while discouraging weeds. Gardeners also can add slow release fertilizer, a mild chemical fertilizer or an organic fertilizer for plants to feed on more quickly, while the compost breaks down.
Luckily, with cool evenings and shorter days, our plants are beginning to slow down and require less water. However, we still are hitting 90 degree temperatures every day. That kind of heat evaporates quite a bit of moisture. We must continue to be vigilant about our irrigating.
As the daytime temperatures decline, this becomes one of the best times of year to be out enjoying our gardens as we prepare our plants for the next season.
Jackye S. Meinecke is a freelance writer and garden consultant and designer. To contact her, e-mail firstname.lastname@example.org or call 323-0903