For all information about our climate visit www.meteo.cw.

Here we mention those climactic conditions which are important for the landscaping of your garden. In general Curaçao has a semi-arid and very windy climate with an average rainfall of only 550 mm/year (22 inches/year). There are no high mountains only a few hills with the highest point at 375 m (1,230 feet).

Our rain season is from October till January where 60 % of the total rainfall occurs. Much of the rain falls in heavy down pours and this means that most of the rainwater runs off to sea. Some of it is collected in man made collection areas, where the water gets a chance to drain into the ground, but where most of it evaporates at a rate of 7,1 mm per day (0,28 inch). Our yearly rainfall is subject to the effects of El Niño. Every 5 to 7 years we have a very good rain year. The last one was 1999 when over 1.100 mm (43 inches) fell. But on the other hand we experienced three years of less then 300 mm (11 inches) prior of 1999.

The wind is a mayor factor to keep in mind, when gardening in Curaçao. Our average maximum wind speed throughout the year is: 45 km/hour (28 miles/hour), while the average wind speed is still a good 25 km/hour (16 miles/hour). And on average the wind direction is from 088º (from the east) 90 % of the time. 
It is sometimes necessary to plant windbreak hedges or place wind break screens to be successful in gardening in other areas of the yard.

The average maximum temperature for Curaçao is 31,0º C. (88º F) and the average minimum is 25,3º C. (77,5º F), which is high for night temperatures. Because of the small difference (5,7º C) between day and night temperatures and the high night temperatures the plants do not get to ‘rest’ and therefore keep growing. The effect for example of this on St. Augustine grass is that it needs to be mowed twice a week to keep it manicured looking in the gardens of the Marriott Hotel here in Curaçao, while in San José, Costa Rica the same grass is mowed only once in two weeks. 
The average minimum temperatures there are 15º C (59º F) with 11º C difference with the average maximum temperature of 26º C. (79º F). The same is true for cutting and trimming plants. It simply never stops. Garden maintenance is a weekly task if you want a ‘tropical looking garden’. These notes are important to understand why garden maintenance in Curaçao is so labor intensive and thus expensive.

While people living in areas out site the tropics (north of the tropic of cancer or south of the tropic of Capricorn) will always keep in mind where respectively south or north is, in respect to the position of the sun, when they design their garden. Gardeners within the tropics do not need to. Simply because the closer you are to the equator the more you will have the sun right over you and about as much sun in both the north and south side of their garden. Curaçao is at 12º North and thus we have the sun twice a year overhead of us. In April when the sun is ‘traveling’ north and in august ‘on its way’ south. Still, some plants will show ‘signs’ of our ‘winter’ period. For example Bougainvilleas planted against walls on the north site of a building will flower less then in our ‘summer’, when the sun is north. On average we have 8,4 hours of sunshine per day.

(Well) Water

When gardening in Curaçao you probably need a well to pump water from in order to irrigate the plants. The other options are: municipal water which is very expensive NAfl. 14,00/m3($ 0.03/US gallon), in cisterns collected rain water (won’t last very long) and septic tank water. The latter is of course very dirty water, biologically and mechanically. Only a very well designed filter system will keep your drip irrigation system from getting clogged all the time. This water smells of course very bad and is full of bacteria.

The quality of the well water varies from garden to garden and even from well to well. In general this water always contains calcium carbonate, which turns everything white when pumped through sprinklers into the wind and onto the grass: neighboring plants, windows, tills, walkways, fences etc. Further the pH (acidity) of well water is always high. The pH of, in this case water, is a figure between 1 and 14. A pH of under 7 means the water is a little acid (pH=6) to extremely acid (pH=1). While a pH of over 7 means the water is alkaline.
Our well water has a pH of 8,5 and so it it alkaline. A high pH in the soil prevents some plants (Ixoras, Heliconias) from taking up elements like iron and boron into their system. This results in yellowing of their leaves. Rain water on the other hand has a pH of 6 or lower (acid).
Rain water therefore dissolves the elements in the soil and makes them available for all plants. Our plants always do better in the rain season, simply because of the lower pH in rain water. Our municipal water is distilled sea water and is of excellent (drinking) quality. Like rain water it has no salts in it so you may think it is good for the plants, just like the rain water. Municipal water, though, has a pH of 8,5 to 9,0!! So it has the same negative effects on the elements in the soil as well water.