Is your grass now looking a little ‘forlawn’?
With temperatures on the rise, lawn grasses, as well as lawn weeds, should be very active.
During the cooler months, winter weeds have been seen in abundance and will take time to become dormant if they are not killed off. So, with summer weeds emerging and many lawns still being invaded with clover, oxalis and capeweed, it is time to take charge if the grass is to be saved from further invasion.
Three grasses are grown on Bermuda's lawns each summer; Bermuda, Floratam St Augustine and Zoysia are diverse in their maintenance requirements.
When starting a new lawn consider the maintenance required to keep it in “good shape” and weed-free. Bermuda grass is usually started by seeding at the rate of 2lbs per 1,000 square feet. The ground must be level and firmed prior to sowing; the finish should be that a footprint can be seen when walked upon.
To achieve best results for germination, sow seed in two directions when no wind is present. Germination should be seen within a week if conditions are good, ie warm and moist soil. Do not cut until a good coverage is established across the area and then only a “tip” cut is required to encourage tillering of the grass shoots.
Zoysia and St Augustine lawns are started by either plugs or sod. I would suggest Zoysia be laid as total sodding. As it is very slow to take off, maintenance to remove weed infestation — which always happens on bare soil — will be ongoing until plugs have grown in. The cost of the extra sod is offset by the cost of labour, of plugging and aftercare.
St Augustine plugs are best planted in the spring, four to six inches apart. If soil is kept weed-free, it should fill in in six to eight weeks with warm and moist conditions.
Bermuda and Zoysia grass are fine-leaved grasses whilst St Augustine is a broadleaved grass. For the best appearance, Zoysia should be mown with a reel blade mower as can Bermuda grass if it is kept short; St Augustine types are usually mown with a rotary blade mower.
St Augustine is best mown to a height of three inches. Continuous close mowing will create an inferior lawn with reduced vigour and weed invasion, especially with weeds of a “ground-hugging” nature.
Most fine-bladed grasses are mown in a boxed manner, however, if a reel machine with a low-cutting height is used, then creating a striped pattern gives a nice finish.
As with any operation, keep mower blades well serviced and sharp to give a clean cut; blunt blades can “pull” grass on its roots and create problems if persistent.
Weed control is an ongoing exercise and care should be taken when using chemical control as grasses can be intolerant to specific formulations, especially St Augustine Floratem. Always consider the time-worn adage, “If all else fails, read the instructions” — believe me it works! Always check with the sales person if you are not sure, or take a weed with you to identify before purchasing herbicide.
Weed-Out is a herbicide which should not be used on St Augustine Floratam, but can be used on the common variety as well as on Zoysia and Bermuda grass.
If small areas of weed appear, get rid of them by hand, taking care to remove all the root or risk having some weeds revegetate.
Grass, like any living organism, requires nutrients to grow and flourish. When considering a bag of fertiliser, one with 16-4-12, or similar ratio of nitrogen, phosphorous and potassium, can be used to produce a good green sward. It should be applied several times through the growing season, if possible just prior to heavy rain with additional watering after.
• Malcolm Griffiths is a trained horticulturalist and fellow of the Chartered Institute of Horticulture in the UK. He is also past president of the Bermuda Horticultural Society, Bermuda Orchid Society and the Bermuda Botanical Society