By Valerie Barr
Water in the Garden
Water is essential for life everywhere, even in a desert. Aware of our communal changing sensitivity to a drier climate, I do notice that water usage is very much a cultural habit. Someone living in the dry areas of Africa would be understandably shocked at the way we use water here and even in high consuming, large Canadian cities we still have the luxury of unmetered water service.
Luckily, Quadra is a temperate rainforest and we experience heavy rain through the winter months which recharge our water supplies. We acknowledge that we need to cope with very arid summers in recent years. Our water use has changed from the culture of large areas of irrigated green grass to conservation systems which efficiently use water when it is both available and needed for other purposes. Today golf courses practice recycling their water supply with large reservoirs. They use specialty plants capable of removing contaminants, like fertilizer from the flow of water returning into the ground or into holding ponds.
How does this cultural change affect our gardening practices? Everyone has to have water stored somehow whether it is in the deep aquifers under our island accessed with a deep well, or in shallow surface wells. We also use reservoirs or ponds, and all descriptions of containment vessels, to catch and hold rain water.
At our house, we live with two shallow wells: one potable for house use and one non-potable for garden use. The non-potable well dries up each summer, which is a signal for us to take conservation measures with the potable house well. We gravity-feed the non-potable water from the upper well through pipes to the garden, and fill a cedar tank. This tank’s original purpose was for holding water at a summer home at April Point and we have re-used it for the same purpose.
We never sprinkle water through any type of water system. Rather we hand water at the beginning of the season, when the vegetable transplants need help before they are established. Unless it rains, the transplants and direct seeded vegetables need this extra care for their roots to develop. Later in the summer we can trickle water through a hose out of this water tank to achieve a less frequent deeper watering. Other than the tomato plants, which get watered frequently in the hotter part of the summer, there are also two areas of the garden that do not seem to hold moisture as well as other areas, and we keep them moist with stored water.
We are extremely fortunate to be on this property with all of its natural attributes, which we take advantage of to grow our large garden. Perhaps the biggest advantage is that we garden at the bottom of the rocky slope of Heriot Bay Ridge and the natural ground water flows downhill year-round. This natural seepage keeps the subsoil moist and encourages the vegetables to put down deeper roots. Even in the driest summers, as we cringe because the poor plants look dried out, we rely on the faith of getting a crop, even through a drought. We have only once hauled water home for the garden and we still had a good harvest that year. Too much summer rain is a bigger problem for us, since warm weather crops often sag if there is too much moisture and pollinators are not as active.
Whichever way you develop your garden, you need to have a water source that is accessible for the plants. Unless you are a very disciplined gardener and routinely spend time with a hose in hand, it is easy to get distracted by our busy lives and plant care can become too irregular. Raised beds especially need more water attention since they warm up and dry out faster.
Automatic watering systems are not expensive to install, especially if you can do it yourself. There are all kinds of options from porous soaker hoses, to buried ½” polyethylene waterlines which have a great selection of emitters and spaghetti lines available to easily distribute water anywhere the poly line will go. Micro irrigation’s biggest problem is caused when dirt plugs up the emitter orifices. To clean out each emitter head is a time-consuming chore. Using in-line filters with the micro irrigation is worthwhile even if you are using filtered house water. The flexible poly pipes don’t need to be blown out in the fall and I have never seen a de-pressured poly pipe break from freezing.
Timers installed on an outside tap have valves which open and close at pre-set times and operate usually on a 9V battery. These tap timers do not like to be left outdoors in the winter when moisture will invade their working parts, so bring them to dry indoors in October. The timers also seem to have a short life span (a few years), but the labour saved is worth the cost of replacing them.
The more sophisticated and therefore expensive water systems built with in-ground PVC white pipe have valves operated by electrical systems, complete with wired-in controllers. These are for large areas and cost more to both install and to maintain. The buried hard plastic PVC systems need the lines blown out with an air compressor in the fall to prevent underground lines from freezing where water collects.
There are landscape gardens on Quadra that never receive extra summer water and do well through the annual drought because the plants are selected to tolerate the seasonal changes (zeriscaping). Although there are a few edible perennials that do not need summer water, generally vegetables do not fall into the zeriscape category.
There are ways of managing your garden to hold moisture by building a bed designed to maximize water absorption. One method is Hugelkultur where a new bed is built using coarse woody debris underneath the top growing layers. The lowest layers are logs of local trees (Alder would work well) on top of which are placed branches and a nitrogen source. The top layers are soil with a hay mulch to conserve moisture. This would be best built in the fall to start the decomposition process and allow absorption of water in the wet season. As they decompose the lowest layers act as a sponge, allowing water to slowly move into the growing medium as the season dries. For more information stay tuned for Karen Dunn’s blog on building a hugelkultur bed at her property on Quadra.
Water is needed for plant growth. It moves the nutrients from the roots to the leaves and evaporates out of the stomata (or pores) on the under sides of the leaves. The stomata are also the openings for gas exchange: absorbing Carbon dioxide and releasing Oxygen. Environmental stress can be visually noticed in plants if you know what to look for. The stress caused by the lack of water can be displayed by the lack of rigidity (when plants get floppy or bend over) and by a subtle change in colour. Without moisture, photosynthesis is not taking place. I notice a blue tinge to the green of a plant if it needs water. Hopefully we don’t stress our plants too much, too often, and they maintain their sturdy photosynthesis glow.
When then is it an optimal time to recharge the water for the plant cells? This time of year (April), or with dry weather, I water in the late afternoon so that the soil moisture is in place for the plants to begin photosynthesis early the next day. At the end of the summer when there is dew in the mornings which encourages fungus and mildew growth, watering in the mornings allows the plant tissues to dry over the day reducing moisture at night. In the past, watering during the heat of the day was considered the wrong timing. The stomata would allow water to evaporate through the leaves too quickly, damaging the plant. Now research tells us if a plant gets too hot the stomata close and photosynthesis is postponed until it cools. Not watering in the warmest part of the day is still a good idea – why waste water through evaporation caused by heat?
Starting Swiss Chard, Kohlrabi and Brussels Sprouts
We only use a few Swiss Chard plants and prefer the variety ‘Bright Lights’ for the colour in the garden: red, orange, and yellow stems. In the fall, the beet greens compete with the Chard for table space, but later the Chard continues to grow through a mild winter. Although it is recommended to direct sow Chard in late April, I do start them in the house to watch their progress. Chard seed, like the related beet seed, does not seem to get old and will keep germinating for years. Perhaps it is time for a new package next year though.
Kohlrabi is a sweet juicy vegetable that is delicious eaten raw or added to any stew pot. I particularly like it roasted in a spicy oil dressing with potatoes and carrots. The variety that we use is called ‘Superschmeltz’ and it grows into soccer ball sized globes. It is supposed to be winter hardy, but because of rats, I harvest it and keep it in closed totes on the deck until we use it up. It is a bit of fun to have such a big vegetable and these 10-pound wonders need to be shared. When one is cut, pieces are given away to friends. I always need to remember to not start too many seeds.
Brussels Sprouts (tiny cabbages on a stick) are not a plant we grow every year. It is all about the timing for planting them in the garden. We have grown them in the past but they were often covered with aphids, so I gave up. Eating them last year from friends’ gardens has made us want to try this challenge again. I have chosen ‘Gustus’ Brussels Sprouts from West Coast Seeds. This variety takes up to 120 days to mature, so I plan to start them indoors in late April and we hopefully will harvest them in September and October in time for Thanksgiving.
Update on Previous Posts
I have planted out the leeks and two varieties of onions. The leeks are standing straight like soldiers in their rows. A few have been eaten to ground level by an insect or an invisible slug and I am wondering if the eaten ones will send out new shoots. The onions started out being floppy and I have leaned some of them against the soil wall of their trenches. I tend to plant many things at a lower level than the soil surface and with time the trenches fill in and the plant roots are deeper. The red onions were planted first and they are putting up new shoots. The yellow onions seemed more delicate as I transplanted them and may be slower to produce new growth. We are getting light rain this week which may help speed up the process.
The radish of course have germinated, but the turnip I direct sowed are not showing yet.
I have transplanted all of the cabbage and kale into two-inch pots and will start hardening them off outside in about a week. The peppers, eggplant and Aunt Molly’s tomatillos are growing well in their 2- inch pots and I am watching to make sure they don’t outgrow their containers. I don’t want to begin hardening them off until we get consistently warmer weather, sometime in May. The tomatoes, which we purchased, are relegated to outside during the day and brought in at night because of a lack of space under the lights.
The snap peas are growing steadily and I wonder when I will see the first white flower. The darn wire worms killed one of the pea plants by eating its roots. I am seeing more wire worms than I want to right now and wonder how the potatoes are doing with so many visible wire worms in the garden. In our garden, the potatoes are always attacked by this pest.
Next Post I will start basil and cucumbers.
Grant Hayden and Val Barr are happily retired to play in their garden as they like. Val worked in horticulture for almost 45 years and started her first food garden at 18. Grant grew up as a prairie farm-boy and his last occupation was in forestry. He has planted thousands of trees and cut quite a few down as well.