Starting Seeds and Growing Transplants Under Lights Univ

Starting Seeds and Growing Transplants Under Lights Univ. of MD. Extension Your Name and County MG Your email address

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Topics Covered • • • Goals and Advantages Why use transplants Materials Needed Timing Seeding, Temperature, and Light Watering and Fertilizing Transplanting Hardening off Planting in the Garden

Goals and Advantages • • Produce vigorous plants Save money (long term) Plant varieties you choose Ensure disease-free transplants Make transplants available when needed Best use of expensive seed Make more intensive use of garden space

Why use transplants • Earlier harvest • Extend the growing season • Seeds germinate under ideal conditions – Temperature, moisture, light and soil-less mix – Control depth of seed planting – Avoid problems with crusting soil • More intensive use of garden space

Not All Vegetables Transplant Well Relative difficulty in transplanting various vegetables Difficult to Easy to transplant Medium difficulty transplant broccoli cauliflower cucumber Brussels sprouts celery muskmelon cabbage eggplant squash lettuce onion watermelon root crops tomato pepper

Materials Needed • Growing media: – Good germinating media should be loose, well drained and fine-textured. It should also be free of insects, disease organisms and weed seeds – Synthetic mixtures (soil-less) • • • peat moss, vermiculite, perlite, p. H balanced + fertilizer Pro Mix, Sunshine Mix, catalog co. 's mix Locally available Bag or bale Use finer media for small seed

Materials Needed Do NOT use garden soil or potting soil to start seedlings; it is not sterile, is too heavy, and will not drain well!

Materials Needed • Containers: – Flats, trays – Clay or plastic pots – Recycled household items • Cottage cheese containers, styrofoam cups, pie pans, bottoms of milk jugs, yogurt cups, etc. – Peat pots and pellets

Materials Needed • Containers – Regardless of the type of container chosen, it must have good drainage (plenty of holes). – Containers need to be sterile • Previously used containers should be washed with warm, soapy water • Rinsed or soaked in a solution of one part bleach to 10 parts water – New containers do not need cleaning

Materials Needed • Seeds: – Seeds can be obtained from local dealers and seed catalogs – For best results, purchase seeds from a reputable company. – May want to do a germination test on seeds saved from past years or just plant additional seed.

Materials Needed • Seeds: – Fresh seed will germinate faster than old seed. – Consult the seed package for the following information: • • Number of days to germination Planting depth Seed spacing Row spacing Cultural information Disease resistance Number of days to maturity

Good info on most seed packets 13

Materials Needed • Fluorescent light (reflector s/b width of flat) • Heat mat and thermostat • Transparent cover (plastic bag, glass, plastic wrap, clear plastic flat cover) • Labels

Materials Needed • Fluorescent Light: – Use either T-8 or T-5 fixture T-8 is half to one-third the price of T-5 T-8 tube are 32 watt Use tubes that produce at least 2600 lumens Use two cool white tubes or two grow lights or one cool and one warm white • Replace tubes after 3, 000 hours when they loose 10% to 15% of their light output • • – 3, 000 hrs/16 hrs/day ≈ 180 days, depending on usage

Materials Needed • Fluorescent Light: – T-5 fixture • More expensive – Fixture 2 to 3 times more expensive that T-8 – Bulbs 2 to 3 times more expensive than T-8 – Last about the same length of time • Produce twice as much light • Not needed for growing transplants • Does a great job of growing house plants and orchids

Materials Needed • Fluorescent Light: – Two tube fixture one foot by four feet • Will start two flats • Reflector should be one foot wide to cover flat – Four tube fixture two foot by four feet ($42) • Will start four flats – Position lights so that they are 1 -2 inches from the top of the growing plants (closer is better) – As the seedlings grow, the lights should be raised – Provide light for 16 hours/day using a timer

My Light Box

Other examples

Materials Needed • Heat mat – 10” x 20” single flat $25 – 20” x 20” two flats $40 -$54 – 20” x 48” four flats $70 -$80 • Thermostat control $35 • Seeds germinate best at certain temperatures a heating mat will increase/speed germination

Timing • Check HG-16 for planting dates and subtract time to grow transplants from seed packet. – https: //extension. umd. edu/growit search for HG-16 • E. g. Broccoli 6 weeks prior to plant out (April 1) • April 1 – 6 weeks/42 days = February 18 • E. g. Eggplant 8 weeks prior to plant out (May 17) last frost date • May 17 – 8 weeks/56 days = March 20 – Search https: //extension. umd. edu for frost dates • Spring frost dates – Clarksville is May 17 – BWI is April 26 • Fall frost dates – BWI is Oct 17 – Rockville is Oct 1

Timing • A common mistake is to sow seeds too early. • Smaller, stocky plants will adapt to the garden more easily than leggy transplants that already have small fruits hanging on them. • Tomato plants 4 -5 weeks old grow and yield better than older transplants. • Tomato start date – Plant out date 5/17 – 5 weeks/35 days = 4/12

Seeding, Temperature, and Light • Steps to Seeding: – Moisten growing media before planting – Fill containers – Firm the media (leave space at top of container) – Sow seeds at the depth recommended on seed packet • E. g. eggplants ¼ inch • Some seed may need light to germinate – Label each container (plant type, variety, and date planted) – Moisten soil and cover container

Seeding, Temperature, and Light • Temperature: – Seeds germinate best at an optimum temperature of soilless mix in container • E. g. eggplant, pepper 80⁰-90⁰ • E. g. broccoli 70⁰ • See seed packet or Johnny’s Seed catalog – Advantages • Greater germination % • Faster germination • Concentrated germination (more uniform stand)

Seeding, Temperature, and Light • Temperature: – A special warm areas may be needed – Use heat mats with thermostat – In the old days you could place container on the top of the refrigerator, etc. – Media temperature may be 5 degrees lower that ambient air temperature

Germination, Temperature, and Light • After germination – Containers should be uncovered – Lower light to 1 -2 inches above plants – Seeds should be moved to cooler location – Check packet or catalog for this info • E. g. eggplants 70⁰ • E. g. broccoli 60⁰

Watering after seeding • Use a fine mist or place the containers in a pan or tray which contains about 1 inch of warm water • Containers should be moist but not wet • Too much water will cause seeds to rot • If seeds dry out, they won’t germinate • Plastic covers help keep container moist

Watering after germination • Water should be at room temperature • After seedlings emerge, gentle overhead watering or bottom watering is needed • Small delicate seedlings respond well to bottom watering until they are firmly anchored in the soil • If bottom watering isn’t practical, use a fine spray • Alternatively, drill small holes in the lid of a gallon jug, hold over plants and squeeze

Watering After Germination • Allow media to dry between watering, but don’t allow seedlings to wilt • Flat or container becomes lighter as it dries out • Water media only when it no longer feels moist • The entire soil column must contain moisture – Apply enough water so that some drips out of the drainage holes

Fertilizing Seedlings • Seedlings will require some fertilization for best development • Fertilize after first set of true leaves appear • Use a water soluble houseplant fertilizer (10 -15 -10, 20 -20 -20, 18 -12 -6) or fish emulsion at about ½ rate • Fertilize at two/three week intervals.

Succession Planting • Use your lights to grow transplants for succession and fall planting – Succession • Beets, lettuce, leeks, cucumbers, squash, kohlrabi • Permits more intense use of available space since transplants have a 4 -6 week head start – Fall crops planted in August and September • Broccoli, kale, collards, cauliflower, lettuce, mustard • Some plants like broccoli will withstand frost and temperature down to 32⁰ • Use season extending techniques

Seed Starting Date for Fall • First frost date for your area (early October) • Subtract days to maturity • Subtract days to grow transplants • Subtract short day factor (14 days) • Fall seed starting date equals – Frost date - Days to maturity – days to grow to transplantable size - SDF (14 days)

Calculation For Broccoli Days to grow transplants 42 days (6 wks. ) Days to maturity: 55 days Short Day Factor (SDF): 14 days_ No. of days to start seeds 101 days prior to frost date • Sow seeds 101 days before the first frost • Counting back from Oct. 20 the date to sow seed is July 11 • •

Transplanting • If you have started multiple seedlings in a single container, they must be transplanted to individual containers • Transplant after first true leaves have formed • Common mistake is to leaving seedlings in the seed container too long

Transplanting • Gently dig out the seedling by gently holding the leaves (Not the Stem!) • Use a fondue fork or small plastic fork • Place the seedling in an individual cell or pot, at the same level it was planted before • Water newly transplanted seedling • Return to fluorescent lights

Hardening Off • Definition: Hardening-off is the process whereby transplants slow growth and develop greater tolerance to the weather so they can survive being planted into the garden • Is critical for any transplant

Hardening Off • About 7 -14 days before planting into the garden: – Gradually withhold watering (don’t allow plants to wilt) – Gradually expose plants to the outside temperatures. • Place plants in a protected, shady location outside • Gradually move plants into sunlight (and wind) for short periods each day. Increase length of exposure each day. – Avoid fertilizing – E. G. eggplants reduce water and temp. to 65⁰ • Hardened plants will suffer less transplant shock and begin to grow sooner

Hardening Off • Cold frame

Planting in the Garden • Once hardened off, seedlings can be set out it the garden. – Transplant on a cloudy day or late afternoon – Set plants at about the same level they were growing in the pots – If transplanting in peat pots, trim the pots down to the soil level or below – Water transplants in using transplant solution of water soluble fertilizer at ½ rate or manure tea

Planting in the Garden • Row cover – Plants can be covered to protect from frost and bugs

This program was brought to you by Maryland Master Garden Program Your County University of Maryland Extension

Resources • Home and Garden Information Center (HGIC) – 800 -342 -2507 – www. extension. umd. edu/hgic – Search “fluorescent lights” • Grow It Eat It – www. extension. umd. edu/growit • Click on “The Basics” Tab • Click on “Starting vegetables seeds indoors”