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Garden Bed Math

📘 Guides20 guides

Zones guides

What your hardiness zone measures, what it leaves out, and why many zones moved on the 2023 map. Each guide has a checklist and a link to the zone finder.

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Guides

🧰 Problem solverIt froze after the last frost date: how to read the oddsA last frost date is a coin flip, not a promise. How NOAA's 50% and 1 in 10 dates work, how to pick the right station, and which date to plan around.Read the guide
🧰 Problem solverOne corner of the yard frosts first: find and fix a frost pocketFrost in the low corner but not by the house? Cold air drains downhill on still nights. How to find a frost pocket, open it up and plant around it.Read the guide
📘 Know-howHow deep to mulch garlic in cold zones, and when to pull the mulch backExtension pages put 3 to 4 inches of straw or leaves on fall garlic. See how much a bed takes, and when to pull it back, move it or leave it in spring.Read the guide
📘 Know-howHow many bulbs per square foot: tulips, daffodils and crocusTulips and daffodils at 6 inches apart come to 4 bulbs per square foot; crocus at 3 inches, 16. See the extension spacings and count a whole bed.Read the guide
📘 Know-howHow many garlic cloves for a bed, and how many heads or pounds to buyCount garlic cloves from bed size and spacing, then turn cloves into heads and pounds. A 4 x 8 ft bed at 6 inches takes 128 cloves, about 2.6 to 3.6 lb.Read the guide
📘 Know-howHow to read a plant tag: zones, sun hours, size and spacingWhat the zone range, sun icon, height, spread and spacing on a plant tag mean, and how to check each one against your own yard before you buy.Read the guide
📘 Know-howMicroclimates in one yard: find the warm and cold spotsOne zone covers your whole street. Find the warm walls, cold corners and shady strips in your own yard, and log what each spot does.Read the guide
🧰 Problem solverThe tag says zone 7 and you're in zone 6: what you can doFell for a plant rated half a zone or a full zone warmer than your yard? How big the gap is, where it might make it, and how to log the result each winter.Read the guide
🧰 Problem solverBulbs still in the bag and the ground is about to freezePlant them now if you can still dig. Extension pages say most bulbs can go in until the ground freezes. Water, then mulch 2 to 3 inches after the freeze.Read the guide
🧰 Problem solverCan you plant onions in the fall? It depends on how far south you areIn the South, yes: South Carolina plants onion sets September 15 to November 15 on the coast. Up north, bulb onions go in in spring. See each state's dates.Read the guide
📘 Know-howDo garlic cloves need pre-chilling in zones 8 to 10?Garlic needs 6 to 8 weeks below 40°F before it bulbs. Here is what Texas, Georgia and Arizona extension pages say, and when a fridge chill is worth a test.Read the guide
📘 Know-howPre-chilling tulip bulbs for a warm winterWarm-zone extension pages chill tulip bulbs in the fridge for 6 to 10 weeks or longer. Count back from your planting day and keep fruit out of that fridge.Read the guide
📘 Know-howWhat your USDA zone does and doesn't tell youYour hardiness zone is one number: the average coldest winter night. What it covers, what it leaves out, and why many zones moved in 2023.Read the guide
🧰 Problem solverWhen to plant garlic in zones 3 to 5: one to two weeks after the first frostMinnesota and Wisconsin Extension say to plant garlic a week or two after the first killing frost. Find your frost date and turn it into a planting week.Read the guide
🧰 Problem solverWhen to plant garlic in zones 6 to 7, read from your frost dateExtension pages for zones 6 to 7 say October, mostly mid-October. See how that lines up with your first fall frost and when to go earlier or later.Read the guide
🧰 Problem solverWhen to plant garlic in zones 8 to 10: fall, ahead of the first frostGeorgia, Arizona, Florida and San Diego extension pages put warm-zone garlic in from late September into winter. See how that fits your first frost.Read the guide
🧰 Problem solverWhen to plant tulip bulbs in zones 3 to 5Minnesota Extension says mid-September to mid-October, near your first frost. Tulips can go in later, as long as you can still dig.Read the guide
🧰 Problem solverWhen to plant tulip bulbs in zones 6 to 7Extension pages for zones 6 to 7 put tulips and daffodils in from late September to Thanksgiving. Match the week to your first fall frost and the cold.Read the guide
🧰 Problem solverWhen to plant tulip bulbs in zones 8 to 10Warm-zone extension pages plant chilled tulips from Halloween to early January. See the window for your area and why planting later beats planting early.Read the guide
📘 Know-howZone vs frost date: two different numbers for one gardenYour USDA zone and your frost dates answer different questions. See why two towns in the same zone can be 50 days apart, and which number to use when.Read the guide

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