We’ve all heard people say that Hawaii has eternal spring. So, no summer, winter or fall? If you have lived here a while or have tried to grow plants throughout the year, you know better.
As busy humans, we may not be very sensitive to Hawaii’s seasonal changes, but plants certainly know when spring arrives. The days get longer, the overnight lows get higher and rain is more frequent. That’s spring in Kona. Ask any plant.
You may have to get your response by observation, noting that most plants are currently busy putting out new leaves to catch the longer hours of sun and growing new roots to enjoy the warmer, wetter soil. You can get seasonal clues by observing the plant or animal life around you or by checking a calendar.
Early calendars were strongly influenced by the geographical location of the people who made them. In colder climates, the concept of a year was largely determined by dramatic weather changes whereas in warmer countries, with less-pronounced seasonal changes, calendars were often based on the phases of the moon.
Throughout the ages, most calendars recorded the passing of time as it related to the earth’s rotation which determines the sun’s position in the sky and the temperature on the ground below. The Roman, or Julian, calendar was used in Western countries for centuries before discrepancies caused noticeable inaccuracies in its reporting of the sun’s position and seasonal changes. In 1545, the Vatican’s Council of Trent authorized a calendar revision to fix the problem.
When the mathematical and astronomical calculations were completed, Pope Gregory XIII announced that Thursday, Oct. 4, 1582, would be the last day of the Roman calendar. The Gregorian calendar took effect the next day – Friday, Oct. 15. Though an average Gregorian calendar year is still about 26 seconds longer than the Earth’s orbital period, the discrepancy will need 3,323 years to build up to a single day. Until then, we will probably continue to rely on this calendar to inform us of the months and seasons we’re experiencing.
According to the Gregorian calendar, one of the two annual equinoxes is next week. These events mark the day when the center of the sun is in the same plane as the Earth’s equator. This solar position means that the hours of daylight are equal to the hours of nighttime darkness. The solstices occur when the night is longest, in December, and the day is longest, in June.
These divisions of the year are also named for the seasons in which they occur. In our hemisphere they usually signal the beginning of their namesake season. Spring equinox this year is March 20. You may want to look for ways to celebrate the beginning of spring, even if the lovely weather seems like what you’ve been experiencing every other day of the year.
Check local calendar listings at sites such as hawaiihomegrown.net or konaweb.com to see what the season might offer to gardeners.
Historically and culturally, spring conjures images of rebirth, rejuvenation, resurrection, and regrowth. Eggs hold the promise of new life and are definitely associated with the primary spring holiday, Easter.
With all these elements in place, we can declare it officially spring and notice how that affects our gardens and gardening. Citrus fruiting season is ending, which means it’s a good time to prune your lemons, limes and oranges. For plants that bloom or fruit now or later in summer, fall is a better time for heavy pruning. Avocados are flowering and plumeria trees are putting out new growth and buds. Many jaboticaba trees are flowering and some are fruiting. Lots of herbs and veggies bloom and fruit year-round here but watch for growth spurts, new leaves and a display of flowers this month.
Spring is a great time to put in new plants. Although you may need to water them well until our summer rains begin, the season calls for new installations.
Additions and corrections
A reader well-acquainted with St. Patrick’s Day celebrations in Ireland offered some additional information to my column on the subject that appeared here last week. I would like to share the essence of his information.
Lionel remembers growing up in Dublin in the ’40s and ’50s and seeing people wear and revere the Trifolium repens with the distinctive white blaze across its leaflet. This clover grew widely in the suburbs and slopes of the Dublin Mountains.
My description of St Patrick’s Day as secular and generally the celebration of Irish culture differs from Lionel’s experience of the devotional atmosphere of the day. The aura of St. Patrick dominates and gives a benign grandfatherly tone to the day. The main parades are religiously themed.
Catholic Ireland has only been free to celebrate its religion publicly for about 80 years. The strength of the Catholic Church in supporting the freedom of the people, uprising several times from the duress of centuries of British rule, is in some ways synonymous with “home rule” and is celebrated on St. Patrick’s Day as well as on Easter Sunday. Parades with the military in green uniforms, the shamrock as a religious symbol and people wearing Irish independence pins gather at the center of the cities on these holidays and walk with national pride.
Diana Duff is a local organic farmer as well as a plant adviser and consultant.
Tropical gardening helpline
Stephanie asks: The leaves on my lychee tree have dark brown spots that look like velvet. What are they and are they something I should attend to?
Answer: From looking at the leaves you brought in, it seems you have what is commonly called lychee rust. It is actually caused by an insect called the erinose mite, Eriophyes litchii.
The erinose mite is a tiny pest that cannot be seen without a microscope, but its damage on lychee leaves is distinctive and can be extensive. The mites will often begin their attack on new leaves at the onset of growth flushes in the spring. Early indications of their damage are small, wart-like swellings about 1/16 inch in diameter on the upper surface of leaves and light yellow spots on the undersides. The affected leaves become curled and distorted, and the spots develop into the velvety brown spots you see on the underside of the leaves. Heavy infestations can disrupt the ability of the leaves to photosynthesise and may result in some flower and fruit damage.
Several control options exist. If the infestation is just starting, you can prune infested foliage to slow the spread. Be careful not to over prune, especially the new foliage. Limit your pruning to less than 1/3 of the new leaves.
For more advanced infestations, you may need to spray the tree. Wettable sulphur has proven effective against the mite when applied at a rate of 5 pounds per 100 gallons of water on an initial treatment and again every two to four weeks.
Control can also be achieved using a suitable miticide labeled for use on this pest on lychee. Three rounds of spraying at 10- to 14-day intervals may be required. The first spray should be applied as the flush of new growth emerges. This is when the leaves are most vulnerable to attack.
Erinose mite damage seldom kills lychee trees nor does it cause severe yield loss but since it is unsightly and can negatively affect the health of the tree, dealing with the pest in one of these ways is recommended.
Email plant questions to firstname.lastname@example.org for answers by Certified Master Gardeners. Some questions will be chosen for inclusion in this column.
This column is produced by Diana Duff.