6 votes
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Auckland Rural Zone and Confusion about Frost Protection

First, a word on how USDA Hardiness Zones are determined. USDA Hardiness Zones are based on the Average Annual Extreme Minimum Temperature. So, the average of the coldest temperature on the coldest ...
GardenerJ's user avatar
  • 5,879
6 votes

How to safely keep plants in greenhouse at low temperatures

Adding to @Ecnerwal excellent answer - Draped row covers will provide a little additional support by trapping in more heat - maybe 1-3 degrees c - the key would be to take them off during the day to ...
davidgo's user avatar
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6 votes
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How to safely keep plants in greenhouse at low temperatures

Plants grown warm, indoors, will need hardening off to transition to an outdoor greenhouse that's unheated. One aspect you may not have considered with a "simple greenhouse" is cooking the plants on ...
Ecnerwal's user avatar
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5 votes

How low of temperature can hot pepper plants tolerate?

They should be fine as long as it doesn't actually freeze. I grow them in Montana and they are very susceptible to frost, but only if it actually frosts. If the peppers are touched by frost, they get ...
webdoc's user avatar
  • 51
5 votes
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What factors could cause a young oak tree to leaf out late?

Trees vary widely in leaf-out time, oaks are a long-lived species that plays it very safe in order to not die out due to a warm spell. Factors influencing leaf-out include: Warm, sunny location, ...
iAndelin's user avatar
  • 220
4 votes

Auckland Rural Zone and Confusion about Frost Protection

Edible Tree Crop Farm was Dick Robert's pioneering permaculture site in Nelson, NZ before the term existed. A sub tropical climate was created with the use of North (equatorial) facing hillsides, ...
Graham Chiu's user avatar
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4 votes
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Marigold Seeds in Light Frost - Are They Lost?

Had they sprouted yet? If they were still in the soil, they are probably fine (for frost, not freeze.) If they had sprouted (to the point of being above soil), you'll probably see the tops die and ...
Ecnerwal's user avatar
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4 votes

How to safely keep plants in greenhouse at low temperatures

As a resource you can consider Eliot Coleman's The Winter Harvest Handbook: Year Round Vegetable Production Using Deep-Organic Techniques and Unheated Greenhouses which discusses growing in unheated ...
Graham Chiu's user avatar
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4 votes

Bulbs start shooting too early in the year

You don't say what part of the world you're in, but this is more of a problem than it once was in many parts of the northern hemisphere, and there is little you can do about it. It's because of ...
Bamboo's user avatar
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4 votes
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Can young sunflower transplants take a light frost?

Sunflower plants are not frost tolerant, but the seedlings are, they will tolerate down to -3deg C at the cotyledon stage for a brief period; that is why the suggestion to sow 2 weeks before the last ...
Bamboo's user avatar
  • 133k
4 votes

How long after last frost before lawns need mowing?

It's a complicated subject, and to some extent, depends where you are and what sort of grass you're growing. In the UK, I might cut grass in early January, if it looks like it needs it - but only if ...
Bamboo's user avatar
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4 votes
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How to protect pea plants from cold?

I live in Wisconsin, where we also plant when the temps can get below freezing, and I think that you're right to be concerned - 9 F is awfully cold for your plants—according to this sustainable ...
Jurp's user avatar
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3 votes

How long after last frost before lawns need mowing?

When your grass crop looks frost covered, do not step on it. You will easily kill the crowns of some of the grass species. I've seen the footsteps of dead grasses where an owner walked out on his ...
stormy's user avatar
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3 votes
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How to protect a lawn against frost?

Grass is not normally sensitive to frost and is not burned by the sun due to frost crystals. That is because when temperatures are low the plant goes dormant. More information is found here where ...
kevinskio's user avatar
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3 votes

How to safely keep plants in greenhouse at low temperatures

I have gardened for years,too many to count. The most success I have had has been to keep the greenhouse area above 10 celcius at night, water your plants so they do not take up all the moisture when ...
Helene's user avatar
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3 votes

To water or not to water a plant right before near frost temps in mid-Spring?

If you're asking whether the soil in your potted trees is better being damp when you know cold weather is coming, yes, it is, so watering if necessary, preferably in the morning to give the plants ...
Bamboo's user avatar
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2 votes

How can I determine if cactus seedlings are dead?

If they get hit by frost, they will go dark, translucent, and mushy. In a while they will dry off and shrivel. If alive, they will remain rigid, and slowly increase in size as they grow. If you can ...
J. Musser's user avatar
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2 votes

How to protect potted vineplants from cold temperatures?

For the more rugged grape varieties, keep them pot-to-pot and well-drained. You should mulch them both above the soil and around and between the pots. Do not fertilize. Check the soil moisture and ...
Bob the Gardener's user avatar
2 votes

Is it safe to use vegetables which have experienced several frosts?

In addition to finding this question when looking into this, I came across an article from the University of Illinois Extension, which had some relevant information: Probably the concern over eating ...
koyae's user avatar
  • 121
2 votes

To water or not to water a plant right before near frost temps in mid-Spring?

Watered believe it or not. The best solution is to WATER with an oscillating sprinkler BEFORE morning. Watering like this actually slows the already frozen cells in thawing. Fast thaw is what kills ...
stormy's user avatar
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2 votes

Marigold Seeds in Light Frost - Are They Lost?

I'm sorry to say they will not germinate, regardless of last night's grass frost or not. Tagetes or French marigold (which is the type of marigold you've described with those varietal names) are half ...
Bamboo's user avatar
  • 133k
2 votes

What's a good alternative to Incandescent Christmas lights for frost protection?

I would recommend using heating cables, although they cost more than lights. There are heating cables designed just for use in soil, so they'd be weather resistant. You can set them up with a ...
J. Musser's user avatar
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2 votes

How low of temperature can hot pepper plants tolerate?

It depends on how much of a risk-taker you are. Temperature for the weather is taken in the air (rather than ground level). It can be colder on the ground, which is why it can frost when it's up to 41°...
Brōtsyorfuzthrāx's user avatar
2 votes

How to protect a lawn against frost?

I don't know what frost is like in Australia, sadly...but here it is a big deal for lawn grasses. The deal is to NOT WALK ON YOUR FROSTED LAWN. This breaks the blades and crowns and if your grass is ...
stormy's user avatar
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2 votes

Plumbago plant spacing in areas that get frost

Plumbago can tolerate a lot of sun and heat so if its in shade, it might not get as big as otherwise. I think that in this area (central TX) they are treated like a "cut and come again" perennial ...
Beverly Howard's user avatar
2 votes

Does using a fleece cloche hinder plants from getting enough sunlight?

You should remove it during the day; unfortunately, UK temperatures tomorrow are set to drop but hopefully not to below 5degC during the day where you are; unless you're growing something really ...
Bamboo's user avatar
  • 133k
2 votes
Accepted

My marigolds wilted due to frost. Can I revive them?

The green parts of that plant are dead. Only time will tell if the roots have enough energy reserves to regrow, but it's not likely. A perennial that has its top killed by frost may regrow from the ...
csk's user avatar
  • 2,290
1 vote
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During a warm-spell in early winter, can dormant hardwoods survive planting? Even if frozen temps are a day away?

My own experience is that planting the hardwoods now will work, even if the soil freezes soon afterwords. This is one time when planting a potted plant, though, that I would NOT try to break the root ...
Jurp's user avatar
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1 vote
Accepted

Do I need to cover freshly planted strawberries to protect against frost when it is snowing?

No. Snow is a good covering that protect against frost. Snow is made by snow flakes, so there is a lot of air (but also compact, so that such air cannot escape easily) , which insulate the soil. On ...
Giacomo Catenazzi's user avatar
1 vote

Can young sunflower transplants take a light frost?

From the range of temperatures you posted of 27 - 41 F, then it looks like they'll survive if you avoid frost forming on the plants. Maybe use floating row covers and keep them suspended off the ...
Graham Chiu's user avatar
  • 23.3k

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