Know when frost is coming to your vines
Vine Companion checks the next 7 nights for frost and the coming week for downy mildew, powdery mildew and black rot where your vines grow, then gives you three simple jobs for the week. Free, in your phone’s browser.
Type your town. We work it out from 10 years of daily weather for that spot.
Takes about 5 seconds. No email, no sign-up.
- Free core, no card
- No app store, no password
- Weather from MET Norway and NASA POWER
Example spring forecastWhat you see each week
Open the app on Monday morning and you know what the week holds.
Frost risk, night by night
The next 7 nights at your spot, with the cold ones marked. Weather models run warm on clear, still nights, so we keep a few degrees of margin.
Disease risk for the week
Downy mildew, powdery mildew and black rot risk from your local forecast, so you spray when it matters, not by the calendar.
Three jobs, nothing more
Matched to the growth stage of your vines: what to do this week, in plain words.
Example spring forecastReal screen recording
Made for how you grow
Every tool is open to everyone. This is what each kind of grower uses most.
A few vines in the garden
- Frost and mildew risk for your exact garden
- Pruning drawings for fences, arbors, posts and walls
What’s inside
- Three simple jobs each week, matched to the growth stage
- “What’s wrong?” for leaves, bunches and shoots, plus a photo check
A small vineyard
- Blocks with their own variety and size (2 blocks free)
- A spray journal that shows when it is safe to pick
What’s inside
- Heat units and growth-stage estimates from regional weather
- Calculators for bud counts, cluster thinning, the Ravaz index and sprayer mix
I make wine
- Every batch with gravity readings, additions and dates
- Cellar calculators next to each batch, CSV export
What’s inside
- It spots a stuck fermentation and tells you when to rack
- All the garden tools too, for the vines behind the wine
I sell grapes or wine
- Pre-harvest and re-entry dates for every block
- FRAC rotation and a warning when a spray clashes with harvest
What’s inside
- Label data for 63 fungicides from the Ohio State 2026 spray guide
- A season report to print or save as PDF, spray records as CSV
Three things it does that a calendar can’t
Every wine batch, from crush to bottle
Log gravity readings, additions and dates, use the cellar calculators right next to the batch, and export it to a spreadsheet when you want the whole record.
Log my first batch →Real screen recording
Know when it is safe to pick
Tap “I sprayed”, type the product, and the journal shows how long you are protected and how many days to wait before harvest. Label data for 63 fungicides from the Ohio State 2026 spray guide.
Always check the label of your own product.
Start my spray journal →Real screen recording
Prune with a drawing, not a guess
Step-by-step pruning for cane and spur systems, drawn for fences, arbors, posts and walls. Pick your trellis and the age of your vine, then follow the pictures.
Open the pruning guides →Real screen recording
“What’s wrong with my vine?”
A step-by-step guide for leaves, bunches and shoots. Not sure? Send a photo for an AI check (one free each month with a free account).
Check my vine →Honest about accuracy
high-risk downy mildew weeks flagged, checked against Cornell’s NEWA disease model
- We warn early on purpose. About half the weeks we flag come out lower on NEWA. One extra look at your leaves costs less than a missed outbreak.
- Frost warnings keep a few degrees of margin, because weather models run warm on clear, still nights.
- The app is a guide. You know your vines, and the final call is always yours.
Forecasts: MET Norway · Climate history: NASA POWER · Disease check: compared with Cornell NEWA · Spray labels: Ohio State 2026 guide
Help shape Vine Companion this winter
We are opening a small number of Founding Grower places for growers who will use the app through the winter and tell us what to fix before spring.
- 10 extra credits. That is 10 photo checks or questions, on top of the 5 every new account gets.
- A Founding Grower badge on your account, for good.
- New features first. You try them before everyone else and tell us if they work.
Why only a few? A small group lets us follow up on every note and fix what you find before spring.
Claim a Founding placeFree. The code is saved when the app opens. You confirm it after creating your free account (we email you a 6-digit code, no password).
All Founding places are taken. Thank you.
The app stays free for everyone. Open it below and you get the same tools, without the badge.
Open the free appCounted by the app itself, updated every few minutes.
Free means free
Everything you need to grow
Frost and disease risk, weekly jobs, pruning guides, calculators, the spray journal, wine batches and up to two vineyard blocks. No card, no trial.
Photo checks and questions
These cost us money to run, so they use credits: 1 credit each. New accounts get 5 free credits and one free photo check every month. 20 credits for $7, and they never expire.
Selling grapes or wine?
The Vineyard plan adds unlimited blocks, a season report and spray records as CSV, with 100 credits. $189 for 12 months, one payment, it does not renew by itself.
What the Vineyard plan includes →Questions
Is the grape vine app really free?
Yes. Frost and disease risk, weekly jobs, the guides, calculators, the spray journal, wine batches and up to two vineyard blocks are free and stay free. Only photo checks and questions use credits (1 credit each), and growers who sell grapes or wine can buy the Vineyard plan for $189 for 12 months.
Why is it free?
Forecasts, guides and the journal cost very little to run, so they stay free. Photo checks and questions use paid AI, so those use credits. We also earn from the Grape Growing Guide website.
Do I need to download anything?
No. Vine Companion runs in your phone’s browser at app.grapegrowingguide.com. To keep it one tap away: on iPhone, open it in Safari, tap Share, then Add to Home Screen. On Android, open it in Chrome, tap the menu (three dots), then Install app. It then opens like any other app and keeps your journal without signal in the garden.
I am not good with apps. Will I manage?
If you can type your town, you can use it. It asks five short questions, then shows one screen for this week. Nothing to download, no password.
Do I need an account?
Not to start. Everything you log is kept on your phone. A free account (we email you a 6-digit code, no password) saves your records online so they are on every device, and it is needed for the photo check.
What happens to my location?
It is used only for your local weather. The app rounds it to about half a mile (1 km) and sends it to MET Norway for the forecast and to NASA POWER for climate history.
Does it work outside the United States?
Yes. Weather and climate work anywhere. Temperatures show in °F in the US and °C elsewhere. The spray label data comes from a US guide (Ohio State), so always check the label of your own product.
Which grapes does it know?
Close to 70 varieties with details, from cold-hardy hybrids such as Marquette, Frontenac, La Crescent and Petite Pearl to Concord and table grapes, plus an “I don’t know my variety” option.
Your vines, one step ahead of the weather
Free, in your browser, set up in about a minute.
Show my frost datesOr open the app now →
