Comparison

GrowDiary vs HydroponicsCalc

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

GrowDiary

Features
Read full description

GrowDiaries is your all-in-one plant cultivation app, designed to empower growers of all levels. Easily document your grow cycles, track progress, and share your experiences with a vibrant community of over 350,000 enthusiasts worldwide. Access a vast library of over 90,000 grow diaries to gain insights, learn new techniques, and improve your yields. Engage in forums, participate in contests, and connect with official representatives from leading seed breeders and nutrient companies. Whether you're a beginner or a seasoned cultivator, GrowDiaries provides the tools and community support to elevate your growing journey.

About

HydroponicsCalc

Manage your hydroponic garden with this comprehensive tool. Track reservoir levels, mix nutrients precisely, calculate pH and VPD, and document your grow with a journal and harvest log. Supports both US and metric units.

Highlights
  • Reservoir management dashboard
  • Concentrate and EC mixing calculators
  • pH and VPD calculators
  • Grow journal with photo timeline
  • Harvest log and ROI dashboard
  • Light schedule tracker
  • US & Metric unit support
Features
Read full description

HydroponicsCalc is the complete grow-management companion for hydroponic gardeners — from beginners mixing their first concentrate bottles to experienced growers running multiple systems. RESERVOIR MANAGEMENT — FRONT AND CENTRE Your grow systems live on the home screen where you need them. See EC, pH, temperature, volume, and grow stage at a glance. Tap Log to record a reading or journal entry without digging through menus. Get change-due warnings before problems develop. CONCENTRATE MIXER Two modes for every workflow: • Bottle → EC: Enter bottle size and coverage target — get exact gram weights per component, dose rate (mL per gallon), and a live EC estimate. • Target EC → Dose: Enter your desired EC — get the mL-per-gallon dose you need. Supports MasterBlend 4-18-38, Jack's 321, General Hydroponics Flora Series, and more. Save your favourite configurations as reusable recipes. EC CALCULATOR Dial in nutrient strength with confidence. Input dose → see estimated EC. Input target EC → get required dose. An EC reference strip shows typical ranges from seedling to aggressive feeding, accounting for your source water baseline. pH CALCULATOR Enter current pH, target pH, and reservoir volume — get the exact mL of adjuster needed. Supports White Vinegar, Phosphoric Acid (pH Down), Potassium Hydroxide (pH Up), and custom adjusters with calibration mode. VPD CALCULATOR Vapour pressure deficit tracking with colour-coded zone feedback. Input air temperature, relative humidity, and leaf temperature offset — instantly see whether you're in the Too Humid, Seedling, Vegetative, Flowering, or Too Dry zone. GROW JOURNAL WITH PHOTO TIMELINE Document your grows with a date-sorted photo diary. Log observations, deficiencies, feedings, milestones, and harvests — with camera or photo library support. Export a full PDF archive of any journal. HARVEST LOG & ROI DASHBOARD Record wet weight, dry weight, and crop name for every harvest. Track cost-per-gram from your nutrient spend. See yield trends over time. Calculate energy costs from your light wattage and schedule. LIGHT SCHEDULE TRACKER Set your light schedule (18/6, 20/4, 12/12, or custom), log your flip date, and get an estimated harvest date with a countdown. US & METRIC Every calculator works in gallons/°F or litres/°C. One tap to switch — all values update instantly. NO SUBSCRIPTIONS. NO ADS. HydroponicsCalc is a one-time purchase. Everything is included. By HackerHomeLab.com

Screenshots

GrowDiary4 screens
HydroponicsCalc4 screens

Verdict

The call

The clearest difference is price: GrowDiary at Free against HydroponicsCalc's $1.99. GrowDiary also leads on iOS requirement (16.4 vs 26.5). HydroponicsCalc's advantage is ads (none vs shown). On in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

GrowDiary is free to download; HydroponicsCalc costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Scorecard3 real differences · 6 level
GrowDiary versus HydroponicsCalc: the parameters behind the verdict, then further details
ParameterGrowDiaryHydroponicsCalc
PriceFree — better$1.99
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 9 days—
AdsYesNo — better
In-app purchasesNoNo
Monetization—Paid
DevicesiPhoneiPhone, iPad — better
Requires iOS16.4 — better26.5
Further details — not scored
Size46 MB1 MB
Age rating17+4+
DeveloperGrowD soft s.r.o.Douglas Stieber

In-app purchases

None

GrowDiary

No in-app purchases

None

HydroponicsCalc

No in-app purchases

Questions

Is GrowDiary free?
GrowDiary is free to download, with no in-app purchases.
Is HydroponicsCalc free?
HydroponicsCalc costs $1.99, with no in-app purchases.
Do GrowDiary or HydroponicsCalc have ads?
GrowDiary shows ads; HydroponicsCalc does not.

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