Should lavendar be cut down in the fall also? Thanks
In My Garden Blog:
Northern & Central Midwest
October 8, 2009
By
Kate Jerome,
Pleasant Prairie, WI
Keep these magnificent Colorado spruces in tip-top condition with water.
Don't Stop Watering!
Fall is coming! I can feel and smell it, and I know by how the garden is acting that it's coming faster than I want. Although irrigation needs will vary depending of the amount of rainfall in your area, it's time think about watering before winter.
Evergreens, in particular, need an extra boost. They will take up water up until the ground freezes hard, and they need the extra water to get them through the winter in good shape. Once the ground is frozen, there is no water available for the roots.
Evergreen Damage
Evergreens such as pines and spruces never go completely dormant as deciduous plants do, and will continue to lose water through their needles all winter. If they have not stored up plenty of water in fall, the plant ends up with a deficit and the needles suffer.
Most evergreens show this damage as bright orange or brown needles in spring. Once the needles turn this color, they will never turn back to green but will fall off. Some evergreens can recover from the winter damage, but often they will have parts of branches or entire branches that die.
Water Requirements
To prevent this damage, it is simply a matter of giving the plants plenty of water until the ground freezes. An inch of water a week is a standard requirement for most plants, and we've had nowhere near that, even with the recent rains. So, to put your plants in the best shape for winter, start setting up a hose on a slow trickle around the plant's root system.
In most soil types, if you wet it down about 6 inches, that equals about an inch of actual water a plant can use. So, water for forty-five minutes or so, and then take a trowel and stick it in the soil to see how far down the water goes. This is a place to start, and you can adjust your timing accordingly.
Deciduous Trees and Shrubs
Deciduous trees and shrubs can also use a boost in order to keep their metabolism in good shape for next year. As soon as the leaves turn color, though, the plant no longer takes up water so you can let them be. Until then, give the same amount of water as your evergreens.
Perennials
Most perennials also need to be well saturated to go into winter, although lavender and Russian sage are a couple of plants that should actually go into the winter fairly dry. Keep watering your perennials, and make sure to cover them with 3 to 4 inches of mulch in order to keep them from heaving out of the ground during freeze-thaw cycles. The mulch will keep the ground frozen and avoid this damaging process which damages the plant roots.
Join the discussion!
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Pat Stephens | October 8, 2009 | 6:51PM
www.daleharvey.co.nz | October 9, 2009 | 12:20AM
So many of our cherished garden and landscape trees are either native species or hybrids of native varieties that originated in North American forests. And why do they survive so well in the forest, without extra watering and feeding? A pleasant afternnon walk through any woodland will bring the answer to your very feet: it's leaf mulch. The ground throughout any healthy wooodland is covered deeply in leaves all in various stages of decomposition. And yet what is a classic autumn obsession? Raking up leaves and getting rid of them! We might as well be throwing away money! Now would be a great opportunity to make a most rewarding change and start mulching everything permanently. It's easier, much more environmentally friendly, promotes recycling, and saves both money, time and watering.
Kate | October 9, 2009 | 4:31PM
Pat - no - don't cut down your lavender. It's touchy and performs best if left on in winter, and then in spring when you see new growth, cut the old growth down by about half. Once it is in full growth, you can cut out the old stalks.
Kate | October 9, 2009 | 4:35PM
I agree wholeheartedly on the thoughts about leaf mulch. I've advocated for years that we let nature do what it does best - protect the plants. Organic mulch of any kind will help keep the soil moisture and temperature moderated which goes a long way toward plant health. It's also easier to let the leaves fall and stay where they are!